So, if you really love PLD, you can do it. Both AV and CC can be sped run with PLD main tank. There are some significant problems though:
A) Gear Curve: Warrior can speed run tank in full af and a sinlge melded weapon with str on it. You're looking at about 500-600k total to really be prepared to be a main tank on warrior (balmung economy, though i doubt its that huge a difference). At about +40-60 enmity you're good to at least try. PLD, on the other hand, is super gear intensive. We're talking at least a rage 40 belt, +1 wrists, stonewall earring, sentinel boots with IV hp or better, thoromen's purpose, and a sword with +20 rage or more. Maybe ifrit's or mogs, though imo garuda's is the way to go if you can get it. Really, for a speed run where you're gonna have super well geared mnks/blms, you want +100 enmity or more. I'm at 153 and am right on the edge against our best monks. Depending on if you attempt to make or just buy the belt, and how much you want to put on the boots and sword, this is easily gonna run you 10mil. I personally failed 32 double meld attempts on sentinel boots before I finally found a doubld IV pair to buy. +40 Belts usually go for around 5mil on balmung. Along with perhaps blm, pld is probably the most gear intensive class, while war is one of the least gear intensive. Af hat body and legs on warior are jsut plain good, hands are passable, and sent boots are a fairly attainable upgrade over teh af boots.
B) Skill. War just is easier to play. Fewer cool downs and timers, and SC is your big button and its hard to mess up. The irony is to get good at pld in raid you need to raid on pld, which you can only do if they want you to tank for them, which they will only want you to do if you are already good at it. I also found going and finding rank 58-62 mobs to practice on with a dd and whm friend helped me a lot when I jumped back into pld cold for this patch after a while away.
C) No matter how good your gear or skill, you on warrior in the same gear is going to be safer for the group. In ten runs on war you might cause one wipe, on pld it'll probably be 2-4 wipes, and that's 1-3 more runs in 10 that you don't see chest #5. Which in my opinion is selfish. You're asking the group to gamble just cus you feel prettier in a shield, and I personally feel bad about that. Raiding is a team effort, and if you really want to bring your best right now... you bring your axe :<
B is manageable, especially with my practice tip. A if you're rich shouldn't be too bad, though you're really gonna want to have either HDL Body or hands, and you can only get those by raiding which again starts a vicious circle. C however, is for me, the insurmountable problem with pld. I'm just not comfy with asking my team to suffer so I can have a little more fun. If you don't see it that way, or happen to not give a flying frak, then no worries.
Check out my suggestions on how to make pld more viable in the plausible solutions thread and give me some feedback!