It's possible to project players' future attributes - either at an individual attribute level or at the formula (like GUESS) level - using their current attributes, their current WE, their Potential and an estimate of games played per season. In fact, I have it on good faith that a number of All-Time coaches recruit based largely (solely?) on this method.
Remove the guesswork - roll your own projection system. Then you don't have to put this information out there in the forums.