Re: Don't tell me what the statement does.
I'm working on a DoD avionics system project right now. It's large. VERY large. VERY VERY VERY large. (get the point? :-)
Part of our SDP coding standards includes a requirement to put banners like that on all subprograms and packages (C++ coders think package==class. sort of.)
When done properly (which is about 50% of the time IMO), this is the most a TREMENDOUS help when you are told ... "HEY! Flight test just hit a problem with this code that was written 3 years ago GO FIX IT YESTERDAY!"
We also have SDP level requirements that people above were flaming to comment basically once per SLOC. I personsally stretch this a little bit and comment once per block of statements when it makes sense to me to do so.
One thing we do with comments happens during our detailed design phase. This is called PDL, or Pseudo Design Language. We basically put together the outlines of our code packages, but with comments describing what we are going to do in place of the code. This makes it easy to review work and do a massive redesign quickly. After design is over, you fill in code, and leave the descriptions. As long as you wriet go mid-level descriptive PDL, this works really well. If you get people who write PDL that would be valid Ada after you pull the comments, it doesn't work.
Since our code tends to live a very very long time and get handed fro mperson to person to person for maintenance, this level of comments is a great help.