I've been in that percentage that makes well over $100 a month despite an average of only 12 articles a month, so it's not a once size fits all fix. I thought about publishing every day, but I just can't do it. I don't write fast, I have a lot of other things to do, and the quality of my writing suffers if I try to put stuff out in quantity instead of taking my time with each article.
I would get really stressed if I felt I had to publish something every day. I agree with you that consistent, good writing is key. But I don't think it has to be every day. I believe it's important to continue to have fun with it, to be inspired, and to feed our inspiration with days off and other activities.