I'm not sure if your serious or not.
When he's in contact with them at ride height, he's not using them as bumpstops, he's using them as suspension. Think of bumpstops as a secondary/safety system and not a primary suspension system. Thats what shocks/coils/leafs/coilovers etc are for. They...
Ya, I would run at least a 1.5"-2" lift for that. With the assumption that those lifts will take you taller than those measurements compared to stock sagging springs.