100% would be ideal, but by 85% do you mean everyone is almost healthy but not quite (but then again, who is after a long regular season) or we are missing 2-3 players?
Simply put, we can't win without any of the Big Three Plus One. We could probably still win a championship with one big and one bench wing, but it would be difficult.
The only teams that are a threat are the Lakers, Heat, and to a lesser extent the Mavs, Spurs, Magic and maybe Bulls.
The Lakers definitely peaked, but how far have they fallen off?
The Heat can destroy weak teams, but so could the Cavs. What happens in the playoffs when defenses clamp down and a floor general and bigs are needed?
The Spurs are playing out of their minds right now, I simply can't see them sustaining this level of play for much longer, let alone against the elite.
The Mavs are intriguing. They can play D, they are big, they can shoot, they have leaders in Dirk and Kidd (you trust them?), but can they actually topple the Lakers? I think they have the best shot at knocking off the Lakers in the West.
As for the Magic and Bulls, they could be dangerous and knock a good team off, but they aren't winning a championship with their current squads.
When ALL teams are fully healthy, the Celtics appear to be the strongest.
Whether we will be fully healthy when necessary seems to be the biggest question.