According to AL.com (h/t CBS Sports), Bielema, a member of the NCAA's Playing Rules Oversight, proposed a 15-second "substitution period" for defenses after every offensive first down.
At first Bielema might sound like an old curmudgeon, unwilling to alter his pro-style offense and taking it out on all the new-fangled kids with their shiny new formations. A cynic might even say he's seeking a competitive advantage. But actually, just like Nick Saban before him, the new Arkansas coach is worried about player safety:
"[T]he way offensive philosophies are driven now, there's times where you can't get a defensive substitution in for 8, 10, 12 play drives," Bielema said, per AL.com. "That has an effect on safety of that student-athlete, especially the bigger defensive linemen, that is really real."
There's plenty of opposition to Bielema's proposal, though, so he might have some trouble trying to push it through the system. A great number of schools have built their program around no-huddle principles, recruiting personnel that specifically fit that system. Banishing those tactics would put those programs at a tremendous disadvantage.
Ole Miss coach Hugh Freeze, architect of a no-huddle system that has given the likes of Nick Saban trouble, voiced predictable concerns with Bielema's proposal.
"Offensive players are playing, too, the same number of snaps. Are they in danger also?" Freeze told AL.com. "If the offense doesn't sub, the defense shouldn't sub, and that's the way the rules are."
According to AL.com, the proposal also met opposition from Auburn's Gus Malzahn and Texas A&M's Kevin Sumlin, two head coaches who, not-so-coincidentally, employ no-huddle formations. Each one has guided a Heisman trophy winner under their philosophy—Johnny Manziel for Sumlin and Cam Newton for Malzahn, who was Auburn's offensive coordinator from 2009 to 2011.
As of right now, Bielema's proposal is just a seedling, a nascent idea that won't affect the immediate future. Down the line, though, if this continues to be a talking point in the rules community, there's no telling what effect it will have.