That would probably just lead to "Nos" instead of "contingent Yeses" (which really are pretty good if you think about it). It's not like these investors are backing out.
It's often not, though. That's what this whole thread is about. Usually when investors waffle it's because they aren't going to commit anyway; they may think that they should and at one level want to, but their fear gets the best of them.
Maybe we're not talking about the same thing. A "contingent yes" is completely different from a "maybe". The rug guys were the "contingent yes", Google Ventures was the "maybe".
Suggesting "A "no" is significantly better than a "contingent yes"" is bizarre.