If the committee uses solely NET as you state how did St. Johns get in with a NET ranking of 73 and NC State (33rd in NET), Clemson (35th in NET) and Texas (38th in NET) not make it in ahead of them?
Kansas State was a 6 seed based on NET but got a 4 seed. Minnesota a 12 seed by NET, but got a 10. If we went by NET rankings NC State, Clemson, Texas, Furman, Memphis and Nebraska would have been in and St. John’s, Arizona State, Minnesota, Seton Hall, Temple and Ohio State would have been out. Shall I go on? That's 20% of the at large field in direct contradiction to "NET rankings".
I do not discount the value of the NET rankings. Nor am I slave to it. Seems the committee does the same. There are sites that do a better job in calculating SOS than NET (IMO). I believe the one I provided is one of them. Especially being NET critically underweights (IMO) conference tournament results (i.e Michigan State winning the B1G tournament and being the lowest 2 seed).