If the sport is going to keep the significant advantage rule, which they will, perhaps adding a word in the class examples or in the rulebook as examples given would help. It has always been explained that if a shooter obtains a better angle, or closer to the target, or can engage more targets than would have been available it was significant advantage. Perhaps adding the word significant to the examples would help.
if a shooter obtains a significantly better angle, or is significantly closer to the targets then it would be a per shot penalty.
Admittedly it is still subjective, but it makes the RO look for a significant result before they declare a significant advantage.