Okay if you look at my armory right now you would say "No way". If I were to attempt this I would respec holy and swap out a few pieces of gear, it would put me at around 2300 spell power with inner fire, 2500 if I flask/eat/raid buffed. Mana regen is at about 980 but I would hardly be out of the 5SR so my MP5 is somewhere around 390 I think. This is what our group would be:
MT Prot Warrior
OT DPS specced DK
And usually we have a resto druid but he decided yesterday that he is quitting. Our guild has a lack of healers and pretty much everyone runs with their own regular 10 mans but there are plenty of dps available. We also bring a second rogue that is the alt of our raid leader that no one is really happy about as we are all on our mains going for achievements and he doesn't even spec optimal dps to come, so I would hope that if I would be solo healing we'd get a better dps to kill stuff faster and make fights like Loatheb easier.
Stuff like 4 horse, Gluth, and KT if I got frost tombed, our boomkin could help out on healing for parts of the fight. I'd have replenishment, innervate, arcane torrent and I could mana pot(I have never ONCE needed a mana pot since our first ever Naxx). I know this would be a challenge but I definitely enjoy a challenge as Naxx with two fully specced healers is retardedly boring. All but our rogue and lock are in pretty much full heroic raiding gear.
What do you think, is it possible?