I was a T-37 IP at Reese when they brought the T-1 into the mix, and it was sold as a way to extend the life on the T-38s while providing more realistic training for the heavy drivers. I personally don't think it led to the reduction in wash-outs (see below).
FY91 was also the beginning of the "Banked Pilot" program, where we had too many pilots and not enough seats for them to sit in. The AF cut way back on pilot slots (my first full class as an IP at Reese had 6 students for 16 IPs in the flight), which IMHO led to a slightly higher quality of student going through the program because it was more competitive. We definitely had less "problem students" than in the past...
Just one ORF's opinion.