Let the source code say what you are doing, add comments to say why you are doing it

I totally, completly agree with you. There's no worst comments than those duplicating informations given by the code since usual coding practices tend to make forget having them synched.

Until you're not a Befunge of APL developer, the language you code with has usually enough semantic elements helping you to understand what is meant in there.

Nota: English is not my mother longue but I can manage to understand approximatively what is meant here without any comments available :-)