I don't think much will change if they the trims were much closer, it's not going to gain you any power or anything like that.

I wouldn't have them do anything to the computer because they aren't actually infront of the car with that laptop. They would just be guessing and leaving you with whatever they think is right, might put you worse off. Stuff like this needs to be done in car with logging and driving to relearn trims after any changes are done.