When we at the spring seminar Russ talked about pumpkins only getting as big as what the plant would support at the time it's pollinated. (don't know how to say this)
First case - female at 8 feet out. Pumpkin is set and will only get as big as the supporting plant allows so we should terminate growth.
Second case - another female at 12 feet . Now is this pumpkin looking at the support of the existing plant plus the competition of the pumpkin at 8 feet?
If you want a pollination at 12 feet should you cull the 8 footer right away so it doesn't affect the 12 foot.