I do the same thing with commas when editing. They make sense when writing, but if I read the text a few days later I find them annoying. The prose is more fluent with the careful elimination of commas - or sometimes, similar to that "that" editing, it's necessary to re-write the sentence.
Not sure why you are eliminating the commas, do they count against your total word or character count? What do you mean when you say "the prose is more fluent with the careful elimination of commas"? If commas are taking up too much space in your writing perhaps you should eliminate periods too, and really speed up the flow all stream-of-counsciousness-like...
Horse for courses, I guess. I don't see/feel any loss of speed or flow reading text with commas in the appropriate places. I like short terse sentences without 'em, and long prolix sentences dripping with them, depending.
Axelotto
just don't get the comma-hate