I do not run my own shop, but seen the BS from the clowns. You are correct that a piece of paper is not 100% protection, but it does help. When someone wants high compression and boost, it is time to show them the door as they will be trouble every time. Let them build the bomb themselves.
High compression and boost is just fine, I’ve done it and it makes big power. You just have to convince the owner that it won’t run on junk pump gas and it needs a real fuel, like methanol.