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2019 Pomeroy College Basketball Ratings
Full stats are available from 2002 on with a subscription. Also, the 'D1-Universe' page has the rankings of every team in the main categories from the year 1997-today without every single stat. Because it is very hard to find stats that account for varying paces of play, this time period is known as the Tempo-Free era.
What we do know is that '99 Duke is the most dominant team since '97. In most years, the champion does not eclipse 34 adjusted efficiency margin. 2015 Kentucky, the team that won it's first 38 games, is tied for the best of this millennium with a 37 adjEM. Wisconsin, who beat them, had an adhEM of 34, which is high even among recent champions. That was a great year in college basketball. National Champion 2001 Duke also achieved a 37 adjEM, featuring Battier, Boozer, and Jay Will. 1998 Duke AND North Carolina (Carter, Jamison, Haywood, etc.) both reached 35 adjEM.
The other recent teams to achieve at least 34 adjEM are:
2008 Kansas, who beat Memphis in the NC on that miracle 3 by Chalmers (and the Rose missed FTs).
2018 Villanova, who steamrolled their way to the title but lost 3 in 6 games in Big East play but were 33-1 otherwise.
2002 Duke, the Jay Williams led team who were ranked #1 in offense and defense in their year, but lost to an insanely underseeded Indiana team in the S16 by 1 (who eventually lost to Maryland in the final) and were up 6 with 2:41 to go in that game but choked it away with 3 mostly unforced turnovers in the final 3 minutes (and Indiana got a few favorable whistles and bounces)..
2000 national champions Michigan St, led by Mateen Cleaves and the Flntstones, who capped off their 3rd straight Final Four.
1997 Kentucky, attempting to repeat following '96's championship, was Pitino's last year coaching Kentucky and they lost in OT of the NC game.
1999 Duke reached an adjEM of 43. Yes, you read that correctly. They're the only team in the tempo-free era to reach above 37 and they hit 43 even with their loss to UConn. This is the reason why people consider them the greatest team of all time. Only 5 other teams even manged 35 adjEM in the last 24 years, and none higher than 37, but Duke in 1999 hit 43.
So if you don't consider them the best team of all time, it's pretty reasonable to conclude they are the best in the tempo-free era, even with losing the title game to Rip and co.
There's a pretty clear and obvious advantage towards pre-prep to pros NBA draft teams. 7 of the 11 teams that broke 33+ adjEM are from the period of 97-2002 and only 4 came between 2003 and 2019. Of course, I would love to see how 1999 Duke compares to the Tark UNLV teams, or Laettner Duke teams, or 1996 Kentucky, or the Wooden UCLA teams, but it's too hard to objectively compare between eras.