I think we
were disagreeing over semantics and my lack of knowledge of the specific wording of 10-6.
I can see what you are saying after examing the rule closely.
If you didn't have such a strong argument, I might contend that a foul simultaneous with the snap is a spot foul because the player hasn't done anything wrong by his actions. The foul was caused because the ball was snapped and the SNAP is what made it illegal. The spot of the foul is the snap because the snap made the action illegal.
I know I'm reaching
Question is this then: If the NF test has a question like, "An illegal formation is a foul simultaneous with the snap and the foul is administered under the all-but-one principle", how would you answer this? (And wasn't something like this on the test this year? If so, what was the correct answer?)