I'll get straight to the point. My guild is currently 6/8H, with two weeks or so progression on H Spine. We're able to get to the last plate more or less consistently, but what happens after gets a bit hectic. Sometimes enough bloods don't die, sometimes too many die, or sometimes I just get mauled and we wipe. Personally, I believe a fair amount of wipes are my fault, so I'm trying to figure out what I'm doing wrong and rectify it.

1) Blood Craze - Is it worth speccing into for this fight? Personally, the healing doesn't look like it'd really help (3% of my total health recovered over 5 seconds is mighty slow...)
2) Mastery stacking - Currently, I hit CTC and stack as much stamina as I can afterwards. Would it be worth going FULL mastery to get as much +crit block as I possibly can?
3) What's the best way to kill the bloods on the 3rd plate? Currently, I'll just spamming as much AoE as I can (I'm starting to come to the conclusion this isn't the best way) and hoping enough die. Would it be better to use Thunderclap just to keep aggro, but then use a single target rotation to kill individual ones?
4) Clearing bloods during rolls - Currently, we mop up any puddles that happen to be down, then immediately roll. Is it worthwhile to hold off and kill eight bloods, THEN roll?
5) Is it even necessary to kite bloods anymore? Sometimes I can tank it fine, but sometimes it's a bit much (although it's possible healer attention could be diverted at those times).
6) Keeping all bloods on you - I can do this fine until the 3rd plate, then they just come at a rate where I can't afford to spam taunt until they get to me, then put some aggro on them. Is there something I'm missing? Currently we have the MT pick up any I've missing, but I feel this is something we're doing because I'm not picking up the slack I should be.

I'll update with any other questions I feel I need to.