[CecilOne]

There seems to be no disagreement among us that the book says an injured player must leave and the book says nothing about the clock and there is no published contradictory interpretation known to us.

The only disagreement is that our interpreter in MD said that the NFHS interprets the rule to mean the player leaves if the clock is stopped, even if ITOJ the player is not injured. Said it more than once, even after I asked if that was different than the book. None of us think that is a good idea, so let's not get on each other about it.

My guess is that the NFHS might think that officials would only stop the clock for an actual injury, so the alleged interpretation would follow "logically" from their changing the rule to prevent coaches from leaving injured players in the game by not attending to them on the field.

As to determining whether a player is injured, the question "Do you need help?" is my starting point. If yes, obvious. If no, and I feel (yes, subjective) there is risk in the player continuing or they are hiding something, then I treat it as an injury. If there is reason (in my mind) to think I have knowledge of risk to the player, they don't play.

As I said before, there is no real reason not to check or observe a player without stopping the clock, until you determine there is an injury.