This is in the interest of being informed when the Warriors part of the special report inevitably rolls around, since my understanding of warriors is basically "Build wounds->do annoying afflictions-> behead.".
As someone who has never actually played a warrior, and who has only ever experienced warrior combat form the other side, could I bother an experienced warrior or two to give me a rundown on the pros and cons of each knighthood spec, and any crippling shortcomings in each?

Id love this information too so in five years when im a demigod I can more easily choose my spec.

Blademaster gets Pinleg/Impale for hindering.
Bonecrusher gets balance loss/stun for hindering (not nearly as effective).
Everything except Bonecrusher gets bleeding damage.

As a Bonecrusher, my kills are typically through BashBrain or damage. There is BurstOrgans, too, but that's usually healed easily enough.

Warrior on warrior combat is like two kids having a slapfight.

The formulas have been tweaked so much that weapon runes don't do much for how expensive they are.

What about Pureblade/Axelord? Are they at all viable?

Pureblade is about those regen cures for hindering, especially tendons. Unless they preapply regen, you're practically guaranteed an unhindered hit after landing one, which is nice to build up wounds. The two-handed weapons seem to be all about outpacing wound curing and you really have no hope of affliction stacking.

In groups its nice to have decapitate as well - which is warriors only timed instakill (unless you count sacraments for paladins).

I'm a fairly poor warrior, but I've played for a little over a year now as one, and I can give my personal opinions (which people may disagree with).

Group combat is a completely different game, and I can say that the most fun I ever have in lusternia combat is working alongside a group. As a blademaster, a pinleg/impale-whore is everyone's best buddy in a group.

Re: 1v1
Everyone and their mother is going to tell you about spamming morphite and rending until they bleed out. This doesn't work. It doesn't work on anyone who's good enough to eat merbloom while pinned and actually knows to shift their stance and parry when it looks like you're getting a rend-train in. Even when you get one going, mid-top tier people will not die from that alone. You pretty much need to go for greenlocks to kill people at those levels and while it definitely is quite easy to pull off once you got the right wounds and the right poisons, greenlocks require a lot of RNG luck, so you need to keep the pressure strong.
Everyone wants to talk about insta-pins and how it's the worse thing in the world since child slavery. The truth is, 1v1, you won't instapin very many people, and if you did that from the beginning until they died, it's their fault. The majority of the people you fight will require you to be pretty damn good at building wounds in order to get a pinleg/impale train. And contrary to popular belief, once you get someone to heavy gut/chest, you have to SUSTAIN that. Blademasters don't have knockdown at medium or jabs at the head that give stuns or block consumption. All our good hindering really starts once we get pinleg/impale/slithtroat. So you need to build those wounds pretty quickly against another class.
Our arm affs are good, but grip-runes mean you'll never really get someone to unwield unless they haven't invested into shield artifacts. Even if you do, severnerve is a quick smoke cure and they will easily cure out of it and auto-rewield before you regain balance. Collapsenerve is great, but you require severnerve to get it, and it's pretty hard to stack collapsenerves on some people, but other curing systems might be easier to beat than others.

Our chest affs are okay, but generally not worth going for until you get to critical. Heartpierce is just about endgame wounds for someone. If you can start training heartpierces, you know that person is going to die soon.

Blademaster is a good spec, don't get me wrong. It's amazingly powerful in groups, and can be the difference between a guy running away and a guy never managing to get out alive. 1v1, you might really require "moar wounds" before you really get to doing anything to anyone which is achievable with runes and demigod, but before that, you're going to suffer a lot of headache.
I know a lot of people are going to run in with angry-faces and all akimbo for me saying this, but I really do think pureblade is a lot more solid for 1v1. Blademasters are stronger that them in groups.

As for bonecrushers and axelords, I can't say much about them at all, really. I'll say that both are fortunate to have knockdown pretty early, and some decent head jabs. Bonecrusher also does ok if you know your poisons really well (as a little ebonguard showed me), but it doesn't have tendon or pinleg trains to rely on, so the general flaws with knighthood become more apparent with them. These two specs are claimed to be the weakest of the four, but I'm personally not convinced that they're as far behind as people would have you believe.

I wouldn't say one is better than the other either. I've seen people pull off every knighthood spec pretty well, so it really comes down to what you want out of it.

I think warriors are also amazingly flexible for group combat, and with the right knowledge of afflictions and poisons, you can help out your teammates quite a lot.

Axelord is a very mixed bag. We have some really nifty afflictions, and we have access to execute (non-random instakill, requires 2/3 of head/chest/gut be at heavy wounds, and 1/3 at critical). The problem I keep running into with axelord is that against a reasonably competent opponent in 1v1, you're hosed. The afflictions handed out don't really do much for hindering until you get to critical wounds on someone. At critical, the amputates, severspine and crushedchest afflictions are great and potentially big deals. It's just getting to critical wounds that is the problem. Since warrior damage is in the toilet, applying for wounds and using scroll/sparkle for health isn't a big deal. Having access to two stuns (ringing ear and open chest) is great, but folks will be healed up from your one affliction and one poison application before you get back on balance. As Turnus pointed out, with tendon, pureblades typically have that free shot if people aren't preapplying.

I will grant the fact that I have not yet started incorporating my beast into combat, which should hopefully allow for a more effective offense on my part. I wish to make it clear that I am by no means a top tier combatant, thus anything I say ought to be taken with a grain of salt.

Edit: Agree with Rivius on the group thing. In groups, especially with other warriors, warrior is a blast.

Thanks for the overviews. Now: what are the general problems with warrior combat as a whole? My experience tells me that warriors are either non-threats or absolutely deadly, with little middle ground. Basically; a non-demigod warrior with a rune or two simply can't compete effectively. Is this a fair assessment?

Even demigod warriors with runes and other boosts will have to get past parry, stance, rebounding, dodging, miss-rate, random swings, etc.

foolofsound:

Thanks for the overviews. Now: what are the general problems with warrior combat as a whole? My experience tells me that warriors are either non-threats or absolutely deadly, with little middle ground. Basically; a non-demigod warrior with a rune or two simply can't compete effectively. Is this a fair assessment?

Depends entirely on race; if you're not a Demigod, you can't effectively compete unless you're a race that can easily get to 18+ strength without the Demi bonuses. If you can do that and you get runes, then you're able to do some damage, otherwise might as well go home (speed bonus races just don't cut it pre-Demi, strength is too pathetic). So, basically, your options are Taurian, Krokani, or Orclach, along with the weaknesses that they bring along.

Ok, some theory craft for you:

Blademaster. I really like all the info rivius went into. Some other little things you can see if you look for it though I thought was worth noting! I have seen people devastate with arm wounds, double hemiplegy moves into easy severed nerves, yada. Gash chest I believe is the aff I am thinking, causes stun which means if you land it on first hit second is counted as prone while on second hit (or first) It hinders curing. I wouldnt be a blademaster if I got a scythe, but I think blademaster is one of the best off, in part because of 2 poisons per set. Otherwise I defer to rivius in large part, he was rather thorough. PS. Arterys all over is realllly annoying.

Bonecrusher. A poster child of meh GENERALLY. However there are several ways to get this to be pretty brutal with easy access to regeneration hindering through the use of poisons and maneuvers, pretty easy stuns and of course knockdown and winding to buy time, you can usually get to a rather nice position. This is one of the most tertiary based skillsets I have seen though. Add it with necromancy and you might pull a sacrifice, throw it with aeonics and you can get a nice aeon + stun train going, paradigmatics you can easily drop con and the other skill in mind eludes me right now, yada yada yada. Every tertiary tends to give something special of its own flavour.

Pureblade. Regeneration (escorts for hire)'s. Most every affliction you know of from them is based on regeneration. Decap is good though. Most of whats already stated is pretty true.

Axelord: Has alot of potential, also varies a bit based on tertiary. Knockdown is really nice but most areas have kind of sucky afflictions. These take a considerable amount of practice in as they lack the EZ regen and hinders of the others. Your leg based hinder is kind of meh, but having 2 wound based instas is rather nice! EZ to outpace wound curing generally from what I have seen (if I dont hinder you to stop you from running me over D:)

Another, related question: How important to a warrior is Forging? Can a warrior be effective in combat with another trade? How much of a difference is there between regular and master plate, and how large an impact do dwarven runes have?

+10/+10 for plate masterarmour
+7/+7 for forging runes

Not essential, but nice.