Raid Composition

The last piece of the tree primer isn't ready yet, so I'd like to throw some thoughts out there about raid composition, how you choose how many and of what type of player to bring.

In my experience it's been pretty standard in 10 man raids to have 2 tanks, 3 healers and 5 DPS.  For 25-man, the formula has been 2-3 tanks (depending on the raid), 6-7 healers (depending on the raid and the strength of the healers), and 15-17 DPS (depending on the number of tanks and healers).

I've run a couple of pugs lately (VoA and Ony) that have eschewed this "conventional" wisdom and run only 2 healers in a 10-man and 5 in a 25-man.  The 10-man was a VoA in which the raid leader brought me - an experienced but not exceptionally well geared druid healer - and a shaman who had never healed a 10-man raid before, along with tanks that didn't know the fights exceptionally well.

In that situation, I considered our 1 wipe (on Emalon) a success.  I was pushing out nearly 3k HPS and the shammy just a shade under 2.  We lost a player or three each boss, but the raid succeeded and most of the players lost were due to factors unrelated to having only 2 heals, such as tanks unfamiliar with the encounters, or DPS going too fast before tanks had aggro.

The Ony raid was unsuccessful, but a number of factors contributed - the advantage of having less heals SHOULD be that you have more DPS, but we still seemed to struggle at times with killing things fast enough.

I don't have any overriding thought on this more than I wanted to put the question out there - am I being overly careful in thinking we should have better than a 1 to 4 healer to everybody else ratio?  Does it depend on the strength of the healers, or the rest of the raid?  Is the world going to end if anybody answers these questions?  News at 11!

err... Something like that.  As always, thanks for coming, and comments are welcome!