Was John Fox's Mile High résumé as impressive as it appears?

So John Fox is out after four seasons, four AFC West titles and four playoff appearances as the Broncos' coach, taking his franchise-best .690 winning percentage (49-22) with him to parts unknown.
But is Fox's record really as shiny as it appears?
I've broken the 49 wins and 22 losses down into the following splits so judge for yourself:

Regular season: 46-18 (.719), Postseason: 3-4 (.429)
Home: 28-9 (.757), Road: 21-12 (.636), Neutral: 0-1 (.000)
AFC West: 21-4 (.840), Non-AFC West: 28-18 (.609)
AFC: 38-16 (.704), NFC: 11-6 (.647)
Playoff qualifiers: 12-16 (.429), Non-playoff qualifiers: 37-6 (.860)
Winning teams: 17-17 (.500), .500 teams: 9-2 (.818), Losing teams: 23-3 (.885)
Favorite (SU): 41-12 (.774); Underdog (SU): 6-10 (.375); Pick (SU): 1-1 (.500)
Favorite (ATS): 30-23 (.566); Underdog (ATS): 7-9 (.438); Pick (ATS): 1-1 (.500)
Peyton Manning starts: 40-13 (.755); Tim Tebow starts: 8-5 (.615); Kyle Orton starts: 1-4 (.200)

Some notables from the above:

• 75.5 percent of Fox's victories came against teams which didn't make the playoffs
• Fox's teams were 32-5 (.865) against teams which finished .500 or worse, including 25-1 (.962) during Manning's three seasons
• Fox's teams were 0-4 as underdogs in the Manning era
• Three of Fox's four postseason losses came in games in which the Broncos were favored