I essentially did this in college for my freshman comp english class.It wasn't groff, or even Unix, or even a screen editor.
It was some RUNOFF clone running on NOS, using the XEDIT line editor.
But once you added the few commands you need (page size, margins, double space), it was just blank lines demarcate paragraphs and you're off to the races.
The advantage here is that one of the things that actual Wordstar brings to the table is formatting. Few of the other just "editors" offer that. (Notably, things like double space). I would not like to have to maintain double space text in a random text editor.
Since the text formatter dealt with word wrap and pages and everything else, I was just able to dump in raw text, not worry about formatting (at all), and just go. It's "OK" to have a line with just a single word on it, so using a line editor really isn't an issue. (Joining lines in XEDIT is kind of a pain in the neck.)
The teacher was kind enough to accept my papers from dot matrix printers on reversed green bar paper (cut to width, of course).
But, fundamentally, using simple groff is very capable for basic manuscripts without having to fall down a deep dark rabbit hole.