I have to be honest: I dont see the problem of including the entire signature at the top of the doc, and the listing the params below. If I know the class/function, a quick look at the signature is often all I need, so I find it convenient that it's at the top of the doc. If it's a class/function I'm not familiar with, I just scroll to the bullet points.

I agree on the bit about whitespace in signatures though. Luckily Python allows me to use as many lines as I want within a parentheses.