It took us four additional attempts this evening, but we finally killed Deathbringer Saurfang on 25-man. Looking at the mechanics of the fight one would think this was actually an easy fight to complete, yet the entire rub of it is control of the blood beasts and deciding what to do with the people who get the mark of the champion. If too many people are getting hit by the blood beasts then you end up with too many Marks of the Champion too early and Saurfang either heals too much or you end up losing too much DPS/heals. If you can maintain discipline, and not allow the blood beasts to get "stuck" on the melee and can kite them well enough and not allow anyone to get hit, the fight is really in the bag.
This boss kill was a hard one coming for us, probably taking about 10-12 attempts, but we did it. And none too soon with the next wing opening in seven days.