Did some research and I agree with you. Turns out there is a new variation on Tommy John with a significantly faster return time.
It is called ‘UCL repair with InternalBrace augmentation’. The return to play rate (RTP) with as good or better results for this approach is also significantly higher (93%), but it is not possible in all UCL tears.
Guessing this is probably what Garrett had done.
Purdy is only the third professional quarterback to forgo Tommy John surgery with a UCL elbow repair, which the 49ers hope will have him ready for the start of the season.
www.espn.com
If he was able to have this type of surgery, and it was done in say February, yes, he might have been able to throw some in preseason camp. The 93% RTP probably drove Dino to say doctors guaranteed he would be as good or better (I doubt they really did that).
Maybe they hoped they could do the InterBrace thing but when they opened him up, it was not possible. Sounds like you can’t know until you have the joint exposed. In that case, GS and Delhomme were on similar timelines and both were not 100% when they returned.
Given the lack of arm strength and accuracy, I think it is fair to say this was a failed surgery. Hopefully GS can get to 100% down the road. Given our situation, I wonder if him might be interested in returning for one more season? Poor guy would probably have to adapt to another system, another QB coach and another OC. He has gone through a lot in his college career.