OK, lets just be clear about 1 thing. This is GM speak, and "I have every confidence" means there is about a 60-40 chance (maybe 50-50). He also said "in the playoffs", not in game 1.
If he really believed Shaq was 100% going to be ready, he would not have made the statement of his opinion.
Really, until Shaq makes it through practice on Thursday, and then wakes up feeling fine on Friday, it is way too early to predict whether he can play.
Personally, I think Shaq will be out there. I have "every confidence" in it myself. But until he actually steps on the floor, it means nothing.