2008: @TCU (ranked #7), @Utah (ranked #2), Arizona (8-5 PAC-10)
2009: Florida State (7-6, ACC), TCU (ranked #7)
2010: @AFA (9-4), @FSU (ranked #17), Nevada (ranked #11), @TCU (ranked #2), @Utah (ranked #23), all with Jake Heaps as QB
2011: Utah (8-5 PAC-12) thanks largely to 7 turnovers, Utah was only up 14-10 at the half.
2012: Oregon State (ranked #20)
2013: Washington (9-4 PAC-12)
2014: Utah State (10-4), Nevada (7-6), Boise State (ranked #16)
2015: Michigan (currently ranked #10)

So, by my count of those losses you listed only three (USU, Utah 2X) were to teams with losing records. Yeah, those are bad losses.

But all the other losses were to teams which ended their seasons with winning records; fully 10 of those teams finished their seasons ranked in the top 25.

I doubt Kyle would have done any better against those same teams than Bronco; in fact, he lost to TCU in 2009 and 2010, lost to OSU in 2012. He's never beaten Boise State, and has only beaten Washington this season.

Unless I'm misreading your post, you're claiming that losses to ranked teams or winning teams from P-5 conferences are "bad losses". Very few coaches would win consistently against teams like that, so I don't see how these losses are an indictment of Bronco's coaching ability.