Ganalane, I understand your thinking - if there was a high level of shorts, we could giggle like schoolgirls watching the shorts have to cover on the way up. If that's your cup of tea.
Unfortunately, that happy reverie is premised on the notion that the shorts are stupid - stupid enough to be short now. But so far, the the shorts have outfoxed all of us.
Given that, I'd rather roar a belly laugh riding in the same truck as the would-be shorts on the way up. They will look just as glum without a good point to sell at - not yet anyways.
So, given that no shorts have volunteered to be stupid and likely won't, the fact that there are no shorts means to me that they don't see a profit opportunity to sell - they, like us, see it going up.