Although most skill players are African-American, a majority of linemen (especially O-linemen) tend to be white or polynesian. I would think that with BYU's recruiting demographic, they should be able to put dominant lines together. Although a rugby player may be poorly suited to the WR and DB positions, they would make great RBs and LBs, as-is. I don't think recruiting is the issue at BYU - it looks to me like development and coaching are larger concerns.

Guys like Wes Welker and Hines Ward are proof that you don't need freakish athletic ability to be a very successful skill player. They have above average discipline, know the game, and run reliable routes. Although BYU may never recruit a Julio Jones-type of receiver, they can certainly coach discipline. Crisp routes, creative playcalling and study/gameplanning for the opponent could mask a lot of athletic deficiency at BYU. Again, I think that comes back to coaching and player development.