Ask YC: How much commenting do you do in Ruby/Rails? (or other expressive language)

When I used to do C/C++/JAVA my code used to be heavily commented, but as I have gotten into Rails I have found myself not leaving much comments and when I try to it seems like a waste of time since I just end up saying "Executing function blah" or some other bit of information that is very evident if you were to read the code. So my question is what commenting conventions people use in rails and have they found like me that ruby/rails generally requires less/no comments. Maybe doing this in a startup means I just try to go through stuff as fast as possible and have become a bad commenter.