I´m sure to that point, James, but know nothing about a discussion about the scale of editing that is eligible.
That must have been more in the past.
My oppinion is, ther should be no more rule than that the original picture must still have to be cognisable.
BTW: How many editing is allowed in the photo contest?
and:
Althought its a fact you may ad to the conditions of the photo contest, that each participant gives his permission to use his picture in the caption contest.