This doesn't have to do with him, but I tried your tip on using gel right at the root for volume, and I dared to blow dry my hair, which I don't normally do. I ended up looking like I had cotton candy hair, lol! Too much body... guess I just need some practice.
He ended up just getting it cut the normal way this time. I think I'll ease him into it over time

If he gets the top part cut just a bit longer each time while keeping the sides groomed, we might get to it soon