Locally we have used starting positions which preclude creeping or peaking.
When using a barricade have the shooter start in the middle so no amount of leaning will expose the target array.Hands in or on marks or holding a rope or other device that is attached to the barrier.
On the subject of ROs with unusual ideas or misconceptions about the rules--I had a strange rule interpretation while attending the Florida state match at Eglin AFB in the 80s.
During the walkthrough the RO explained that due to the low(and just built) berms any time while the shooter was engaging targets and the muzzle went above HORIZONTAL, which caused the gun to briefly point over the berm,that this was unsafe gun handling and would result in match DQ.She also explained that during reloading the gun must point at the ground---not up in the air or over the berm as this is also unsafe and would be a match DQ.
One of the shooters pointed out that every time anyone fired the gun it briefly pointed ABOVE horizontal and would that not violate her idea of unsafe?She agreed that it would indeed be unsafe and we should be sure that it did not happen.
Two shooters hauled out their $100 and said that they were protesting and to get the match director right now.She threatened to have them removed for unsportsman like conduct.The rest of us told her she was out of line and needed to call the director and settle the issue.
After 15-20 minutes things were sorted out (she was sent to the stats shack) and we shot what was a very fun stage.Started with two Kansas double speed setups and proceeded to some very tricky poppers through some high and low ports.
Very good match and beautiful ranges.