Coach may know fundamentals but I also think it will take more than 5-6 guys (added Madsen since he's getting minutes off the bench) to make a run @ the Big 10 title, conference title and get a few tourney wins. If any of those gaurds get into foul trouble the remainder of the year, does he actually expect to get any production from Simmons and Hill if he needs to play them after sitting them both for the majority of the Big 10 season? There have been opportunities to play guys off the bench during this current Big 10 winning streak, especially in their blow out wins against NW and Minny the last few weeks.
IMO, by playing the starters more, he's just giving them more incentive / exposure to bolt early for the NBA, most notably Turner and Buford. Buford is finding his stroke and turning into a scoring machine.
Personally, I like the energy that P.J. was bringing off the bench and Simmons gives them another solid 3 point shooter on the perimeter. I think both have shown enough good things on the court that warrant a few minutes to spell Turner, Deibler, Lighty or Buford during the game or at least in mop up duty.