In 3 seasons Greg has played 0,61,21 games for 82 total games out of 246 possible games or 33%
In 6 seasons Joel has played 76,56,43,77,82,30 games for 364 total games out of 492 possible games or 74%
In 14 seasons Marcus has played 63,63,46(of 50),59,63,29,29,72,66,56,70,79,62,51(of 52) games for 808 total games out of 1086 possible games or 74%
If we expect the same probabilities for these guys to play games next season then the chance that all 3 would be healthy for a single game is .33*.74*.74 = 18%
Next I decided to look at minutes played out of possible games.
Greg has played 1816 minutes out of 246 possible games which is 7.4 MPG
Joel has played 8406 minutes out of 492 possible games which is 17.1 MPG
Camby has played 24,824 minutes out of 1086 possible games which is 22.9 MPG
All 3 of those added together are 47.4MPG or less than the full minutes at a single position of a regulation game.
Notes:
1. For Joel I only included games and minutes played since coming to Portland in 2004, prior to that I don’t believe he was a regular rotational player.
2. Now there is an argument that Greg has a smaller sample size with his injuries so the true probability of him playing is higher than 33%. I’m sure that is a possibility, but it’s also very likely he is injured again or has extreme foul issues so I used the actual data even though I hope he reverses the trend.
3. Joel is going to be coming off a major surgery and will not be at full strength for the start of the year, even when he completely recover he may have difficulty reaching the level of performance as he had attained over the previous 6 seasons. So his probability of being healthy could be understated.