It took me a while to find the "help" button for comments, and we seem to have a steady stream of people who have trouble finding it on their own. I suspect that's because it's floating off in a corner you don't have much reason to look at. Would it be difficult to move it to the immediate right of the "cancel" button, instead of the far right, and possibly rename it "formatting help"?
(I don't know enough python to look at the site's code, or I would check this out myself.)
Definitely move it next to the comment button. I've used it a dozen times and it still takes me a bit to find it, though that's probably the fault of me being scatterbrained as much as anything else. Moving it would be a big help to newbies, who are most likely to need it and least likely to know where/what it is.
Relabeling is probably a good idea too, and I'd suggest "formatting help".