Standard stuff. 4-on-5 and 3-on-4 drills to drill close-outs and rotations. Closing out was easier 20-25 years ago because everybody wasn't a three-point threat like today. Plus the 3-pt line was a foot closer.
Dr. Tom had his presses. He was extremely good at teaching them, and then teaching individual players how to use their individual talents within them. And then each press had intensity variations. For example he would show a 2-2-1 for a few minutes and play it soft, then once he notice the other team sort of relaxing, assuming the pressure was token, he would ramp it up and often get turnovers out of it. Often times they would show press then after one pass retreat to half-court man or zone.
There are all kinds of ways to make teams a little off-balance on offense, a little uncomfortable. Dr. Tom switched defenses, and switched intensities within defenses, to do this. Some rosters allowed him to ramp up pressure more than others. Some players, like Kenyon Murray for example, stand out in this way. Acie, too, because Dr. Tom trusted him so much as a back line defender.
So there was a lot of work in practice on the different defenses, and their different approaches, in scrimmage break-downs.
I was only there a year before I decided I would rather pursue a scholarship than be a walk-on. In retrospect I wish I had stayed. Transferring all over the place, well, there is something to be said for continuity — for staying in one place for college. I really enjoy watching old Iowa games from Dr. Tom days, and I am struck by all the little coaching nuances I pick up all these years later. He really was a very unique coach, a unique mind for the game.