Well, if he wants it to be his living, then yes, that's exactly what he needs to do. Hell, if he makes a name for himself at Marvel or DC, then sales on his pet project might increase along with his name recognition.
IMO, there are only two ways to EVER make a comfortable income creating comics. Work for the Big Two, or create something that gets optioned as a movie or TV series. Otherwise, your comic craft is most likely only ever going to be a side job.