People thought Stull would help the Gophers because we had previously struck gold on Springs from the same team and league. They put up similar numbers, so there was at least data to drive some optimism. But I think you're pretty far off-base trying to correlate Stull with either Willis or Carr here.
But if I wanted to counter your point with an actual sit-out transfer, I could say people thought Stockman was going to be a waste of roster spot coming into this year and were very down on him. But then he exceeded all of our expectations and was actually quite impactful in a number of important games (and definitely should have been getting more minutes throughout the year).
Or Reggie Lynch was expected to be a good defensive player coming from Illinois State. Lynch, however, ended up being one of the best defensive players in the Big Ten and was a huge force in the middle. When Lynch was suspended, it was an important part of the implosion of that year's team and we never recovered.
As far as Davonte Fitzgerald (because surely someone will bring him up), he was said to be one of the best players on the team in practice his sit-out year. But then he had a second horrific knee injury and was never the same.
So...based on that (actual) sit-out transfer data, I'd speculate that we can expect positive impacts from both Carr and Willis this coming year. The only sit-out transfer in recent years that we do NOT have hard game data integrity for is Fitzgerald because nobody outside the program saw what he looked like previous to that 2nd knee blowout.
