MacLeod: 2 conference finals and one NBA finals
Fitzsimmons: 2 conference finals
Westphal: 1 NBA finals
D'Antoni: 2 conference finals
Gentry: 1 conference finals
Here's who they lost to, with champions in bold (depressing):
MacLeod:
'78 Bucks, '79 Sonics, '80 Lakers, '81 Kings, '82 Lakers, '83 Nuggets, '84 Lakers
Fitzsimmons:
'89 Lakers, '90 Trailblazers, '91 Jazz, '92 Trailblazers, '96 Spurs (took over for PW)
Westphal:
'93 Bulls, '94 Rockets, '95 Rockets
D'Antoni:
'05 Spurs, '06 Mavericks, '07 Spurs, '08 Spurs
Gentry:
'10 Lakers
I'm not necessarily sold on Westphal and D'Antoni's lack of success elsewhere as a huge factor for my evaluation. I'm hard pressed to think of that many coaches who've had success with multiple franchises without elite talent around them like Phil Jackson and Pat Riley have had, for example.
Doc Rivers looks like he's on his way. Lenny Wilkens, Larry Brown, Don Nelson, and Rick Adelman. Who am I missing?
After Seattle, George Karl took Milwaukee and Denver to the conference finals once each, but lost in the first round the rest of the time.
Of course, it seems credible that single-team coaches like Gregg Popovich (obviously) and Jerry Sloan would have been able to have success elsewhere with their systems in place.
But unfavorable comparisons to many of the above don't make Westphal and D'Antoni terrible in my book. I just wish they were in the list of coaches with a championship, or better yet two like Rudy T. Ouch those Rockets losses still sting...