I've definitely always made more from commenting than I have posting.... and that's because your articles were some of the first posts I read on the Steem Blockchain. I've also gained way more followers through comments than posts... which makes sense given that you can really only reach the people that already follow you with your posts.
Sometimes a whale will randomly upvote a comment I make, which can be several times the amounts I usually make on posts, but generally its a numbers game, lots of little upvote amounts.