Every year I look at which leagues played above and below seed. Last year Pac 12 was the best I have ever seen by miles, this year again the "down" conference ACC obliterated its seeding.
Big 10: -1
Lots of low seeds that couldn't possibly underperform seed, still couldn't get into positive territory in spite of great setup
Indiana, even
Rutgers, even
Michigan, +2
Michigan State, even
Iowa, -1
Illinois, -1
Ohio State, even
Wisconsin, -1
Purdue, even (couldn't beat a 15 seed to get to elite 8)
Big 12: even (Baylor's 1 seed second round loss is a killer)
TCU, +1
ISU, +2
Texas, even
Tech, even
Baylor, -3
Kansas, even (can get to +2 if they advance to champion or +1 if make title game)
SEC: -7
Ark, +1
Alabama, -1
Kentucky, -3
Tennessee, -1
LSU, -1
Auburn, -2
Big East: even
Uconn, -1
Marquette, even
Seton Hall, -1
Villanova, +1 (has a chance to add one or two)
Creighton, +1
Providence, even
ACC: +8
second year in a row "worst" conference severely underseeded, last year was Pac
ND, +1
Duke, +1 (can add 1 or 2)
UNC, +3 (can add 1 or 2)
VTech, even
Miami, +3
Pac 12: -3
UCLA, even
USC, -1
Arizona, -2
MWC: -3
0-3 with slightly better seed in all 3 games
CSU, -1
SDSU, -1
Boise St, -1
WCC: -2
Gonzaga, -2
St Mary's, even
SFU, even
American: +3
Houston, +2
Memphis, +1
A10: +1
Richmond, +1
Davidson, even
total
ACC +8
American +3
A10 +1
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Big 12 even
Big East even
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Big Ten -1
WCC -2
Pac 12 -3
MWC -3
SEC -7
Most interesting that all 3 western leagues struggled after Pac 12 obliterating their seeds last year. SEC had a high seed dropped immediately, but unlike Big 12 the rest of the conference didn't pick it back up. ACC was clearly much closer to the typical ACC than people thought.