If you are noticing on certain holes, maybe the point of the ball landing is not as favorable as when you were pro landing possibly in better positions that take a nice hop.
I dont doubt what you are saying, but I had the rapture, and rarely average anything more then 260-265. Longest drive with it was 309. and like goldcard wrote your stats suggest 258, but not sure how much of that was the rapture vs when you were amatuer.
It has also been mentioned that WGT will adjust the speed of the fairways occasional, so maybe its a combo of non favorable landing zones and softer fairways.