For a lot of people, this may be common knowledge, but I've encountered quite a few tanks (mostly talking to the Paladins here) that didn't know about these few helpful tricks to make an Amdapor Keep run go more smoothly. These can, of course, be applied to various other situations in the game.
-Shield Bash will interrupt the casting from the lunatic summoners trying to summon demons. Silence will not work, however.
-Hound Lights (the little blue balls) CAN be slept. Tauri (the horned evil lookin' things usually in groups with Hound Lights on the first floor) cannot be slept. Keep this in mind if you have a mage that will lay out some crowd control.
-From the moment they are aggro'd, you can get off two full Rage of Halone combos before Dullahans will use Iron Justice, which you can easily shield bash and continue killing without moving.
-The Psychflayer (first boss) can have all of its moves interrupted by Silence. Using Spirits Within to silence Mind Melt will help your healer immensely. Everything can, of course, be stunned, but Spirits Within isn't on the GCD and can be used in a pinch.
-Also on the Psychflayer, Void Thunder III can be avoided completely by moving behind the mob. As with all mobs who cast spells, their casting will be interrupted if you are not in their line of sight when their cast bar is finished filling. Obviously this will prevent you from taking big damage and take another load off your healer.
-Shield Bash on the golem that uses "Obliterate" will, once again, help out your healer greatly. Being able to Silence Mind Melt and Shield Bash Obliterate will almost make your healers job boring.
-On Demon Wall, use Sword Oath until the Wall prepares its second Repel. Switch to Shield Oath as it's charging then proceed to tank the Gnats as necessary. PLDs aren't known for their DPS, but every little bit helps and at level 50, Sword Oath is a damn fine addition to damage. Also during this time, use Tempered Will to prevent yourself from being knocked back, leaving you right next to the adds. Be advised that you'll still need to move back a bit, or the Wall will overtake you and warp you back to the door of the fight area.
-If you use a mage or BRD to pull any of the Succubi, be sure to have Shield Bash handy. Even after you take hate on the actual enmity list, some Succubi like to pursue the original puller to cast Void Thunder III.
-On Anantaboga (final boss), there is a sweet spot near the back right torches that you can stand and tank, never having to move. This spot can be denoted by a line in the floor with rubble on one side and clear on the other. Standing here makes it easy for everyone to hide behind the closest statue (which is the last to transform) and still keeps the same statue between you an Imminent Catastrophe. You, nor the boss and sometimes not even your healer, will have to move and it keeps the room clear of Tail Swipes when running orbs around.
Thank you for your time, and I hope this helps some beginning tanks out.