That has been clearly demonstrated by the draft. Both from an age and "lost opportunity" standpoint and because of less "cultural fit" (see the article about the Florida State player on a Rhodes scholarship).

To get a fair chance to even make the team as a BYU player and return missionary you have to be exceptional, at least above the level required for non-LDS players.

Those are just the facts that have to be accepted by kids that choose BYU and missions. And it won't change.

And that doesn't mean BYU can't improve in both recruiting and player development. But the cultural and mission issues are the biggest ones.