I don't think the high value prospects are going to spend that much time in the minors compared to the days of old. The Harper's and Strasburg's of the world will play enough minor league baseball to learn the team system and get plugged in quickly as long as there is room.
Yeah, but guys like Harper, Strasburg and Mike Trout are generational talents. They are hardly the norm.
Triple A is no longer the proving ground for the high end draft picks. Triple A is pretty much a holding pen for veteren players trying to make one last run and those back end prospects that will most likely scrap away for the remainder of their careers hoping to join the parent team as a fill in for an injured player or as a late season roster addition. A good season in Double A can pretty much get you that spring training invitation and eventually a roster spot.
This is silly. Just taking the Cubs as an example, you only need to look at Corey Patterson, Felix Pie, Josh Vitters and Hee Seop Choi and now Starlin Castro to see players whose careers were ruined due to inadequate time in the minor leagues. A player doesn't get drafted and magically learn everything they need to know at AA, where the competition is laughable and many of the stadiums are launching pads. AAA is far from a place for veterans and scrappers -- it's probably the most important part of a player's development, because it's the closest he gets to major-league pitching / batting without actually getting thrown to the wolves.