re: For block comments
In my view block comments of code need to have a marker at the start of each line so that when they appear without context, eg via grep or other search tools, it is still obvious it is a comment. That marker can be as asterix, I guess, but I just use // for all comments. My text edit makes it easy.
I also let the text editor wrap long lines, so I only need one // per paragraph, making it easy to edit. Using hard line breaks is a bad idea when you are editing in a window that might not be exactly 80 columns wide.