However, in your scenario - the initial step climb is to 4 which you've reported climbing to and the controller has confirmed the same alt. As far as I can tell, you haven't been taken off the SID (Unless the controller said to maintain 4000 on reaching) and therfore should continue with the step climbs as published.
So what you're saying is that when the pilot hears the words "climb to altitude 4000 ft", he should look at the SID to work out if that's what he's expecting to do or not? If it's in accordance with the SID, he should continue with the step climbs. If it's not in accordance with the SIDs he should maintain 4000 ft until further cleared.
Sounds like a recipe for disaster to me.
