Stan Prevost wrote:



I have never received a clearance for just "VFR On Top" without further
restrictions, although I understand it is permitted.

I can't understand why you'd restrict an aircraft, outside of a class B.

Restrictions can be
"Maintain VFR On Top at or below xxx", "....at or above xxx", or "... at or
between xxx and yyy".

Yes, but what's the point? I don't have to separate you so why restrict
you?



I understand that the controller is not responsible for separation, so I
wonder why I always get an altitude restriction, usually "at or below".

Ask next time.