Very very few players had the physical attributes Victor has coming into the league and it's practically unheard of for someone his height and weight to be successful in the nba long term as a team leading superstar (i..e not Boban/Manute Ball like contributor). I think the Spurs are very aware of that and are taking every precaution to shield him physically until they have a better understanding of his potential durability within an NBA game.
I believe we are going to see a lot of "first time in the nba" type of actions from the Spurs when it comes to Wemby, simply because he is so unique and will require a unique multi-year plan to get him to where he can potentially be, which is (some say) the best player in the league.