2008 vs Dallas - 4-1 Win (NO was favored)
2008 vs Spurs - 3-4 Loss (not sure who was favored here but they both win 56 games)
2009 vs Denver - 1-4 Loss (Denver was favored)
2011 vs Lakers - 2-4 Loss (LAL was favored)
2012 vs Grizzlies - 4-3 Win (Clips were favored)
2012 vs Spurs - 0-4 Loss (SA was favored)
2013 vs Grizzlies - 2-4 Loss (both teams won 56 games)
2014 vs Warriors - 4-3 Win (Clips were favored)
2014 vs Spurs - 4-3 Win (Clips were favored)
2014 vs Rockets - 3-4 Loss (Both won 56 - I think Clips were favored tho)
2016 vs Blazers - 2-4 Loss (Clips were favored)
2017 vs Jazz - 3-4 Loss (both won 51 games)
2018 vs Wolves - 4-1 Win (Houston was favored)
2018 vs Jazz - 4-1 Win (Houston was favored)
2018 vs Warriors - 3-4 Loss (Warriors were favored, but this was a choke even if he didnt play games 6 and 7)
2019 vs Jazz - 4-1 win (Houston was favored)
2019 vs Warriors - 2-4 loss (Warriors were favored)
2020 vs Rockets - 3-4 loss (Houston was favored)

And then his Phoenix career. So - there are 2 or 3 series you can maybe point to that he SHOULD have won, but his "underachieving" status is so beyond exaggerated.