What i am seeing here is that other players refuse to play as a team. I also main WAR and my wife is a SCH. But when we group up and run dungeons, we are very clear cut on how to treat certain DPS. As the tank, if you are in a 4 man dungeon, take a quick second to assess the other other players' jobs and gear. While not 100% true, you can usually figure out how your run will be right at the beginning and adjust your style accordingly. Even then, sometimes some quick communication is always a good thing. For example, if the party looks like they are extremely high iLvl and you aren't sure if you can handle big pulls, then just let them know. After the first one or two trash fights, you can get a pretty good idea on how the rest o the run will be also.
Another example, if you get a BLM & BRD in your pt, be ready for a lot of AoE damage. Don't bother marking. Grab a mob, Flash, try to get 2-3 Overpowers in, Infuriate, then Steel Cyclone. That should give you plenty of starting emnity for the mobs. From there start working on rotating your Butcher Block combo around while watching the aggro bars for any spikes. Overpower of Flash occasionally if you have to, and keep Steel Cycloning for that hate.
Other times, you get DRG's and MNK's, this is where you got to keep your eyes open. There are many DRG's and MNK's that will go balls to the wall right out of the gate and produce some stupid high numbers right at the start. Times like this, you should probably watch the first fight and see if they like attacking different mobs than you are. Start marking if they become a problem. If they continue to attack the wrong mob, let them have it. Remind them when they are either dead or near dead that the markers are there for a reason. Most DRG's and MNK's have very high wait times for roulettes, so they tend to listen.
In 8 man parties, if there is a PLD, you are likely to be the OT. this is when you simply watch your own hate. I personally keep Defiance up to have my self-healing moves (Inner Beast) available. Inner Beast is also a Buff, so it lowers your incoming damage as well from any random AoE's. Also, having a Steel Cyclone ready if adds pop up is very helpful. If you are OT though, don't use the Butcher Block Combo. I alternate between the Storm's Eye Combo, and Storm's Path Combo. Storm's Eye decreases target's slashing resistance by 10%, giving the PLD MT an extra little boost.
Provoke is your friend, believe me. If a mob goes astray, 'Voke it and IMMEDIATELY use another emnity move.
If a person in your party gets hate and runs around or away like a 'tard, that's on them. Smart DPS's or healers run at the Tank when they get hate so the tank can get it back without risking the rest of the party.
Also, if a CNJ/WHM uses the stupid water blast in a fight, or Carby/Garuda does the move that pushes a mob away, tell the offending player to stop it. Having to run after the mob and reposition it for the melee is a pain in the ass all for one little move that does minimal damage.
Most importantly, remember, if you are the MT, YOU ARE IN CHARGE. You know your survivabilty better than anyone else. Work with your healer to establish a good flow between you two. Once established, good DPS's will usually flow right in with you and you will have an excellent run.
Good luck and happy gaming!