My main is Cloudhoof on the Arygos server, not this Paladin anymore.
Anyhow I just switched from a 0/24/37 to a 6/21/34 build (
http://www.wowhead.com/?talent=cxoZVVbRVzZchhGzfMhVzh) for max DPS i would have gotten the 2nd point in focused fire instead of scatter but I PvP some too.
I did a few tests over the past few days asking myself the same sort of questions this thread does. Although I have never had MT, I feel pretty sure now IAoTH and FF is better than Thrill and Barrage.
This was after thinking about how I can overcome the mana problems losing thrill brings but its harder to replace IAoTH.
So I tested out on Dr. Boom, haven't gotten to raid since making the switch:
I did 2 mana bars worth for the tests basically, no buffs to myself and no HM
1. With Dragonspine : 697 personal DPS 1:50 avg. until OOM
2. With Blackhands: 617 personal DPS 2:00 avg. until OOM
I was using a full Multi/Arcane rotation with Blackhands and using a full rotation on the other until dragonspine proc'd and then I'd go Steady/Auto.
So once I saw I could handle the rotation switching and saw how much the haste seemed to help I went for IAotH to see if I could increase the damage more.
3. With Dspine and IAotH: 769 personal DPS 1:30 avg. until OOM
Granted more tests need to be run, but after seeing this I wanted to try out in the real world and I'll try to get some of those kind of results soon. I should also end up in some groups with or without shadow priest and can relay what sort of difference that makes.