To me it seems that what changed before&after the dinner, was the publicity it took, which switched Ron Conway from a 'wait&see' approach (at the very least) to the openly hostile approach we saw in the 'nuclear bomb' email.
While before this update I gave Ron the benefit of the doubt (not in small part due to pg vouching), it now seems that he was much less surprised than I thought.
My estimate that the 'nuclear' email was damage control intended to be publicised has just gone up.