That is absolutely how I do it as well. Yes I can sharpen by hand but why?Not arguing, I see many people more experienced than me doing it this way. But I've always favored just swapping to a new chain, throwing the rocked or dulled one into a box, and processing it in my warm shop on some cold evening, versus spending time in the field fretting with it.
There are worse ways to spend a Tuesday night, than sitting at the grinder with a cup of coffee to one side, and a good podcast going thru the ear buds, plucking your way thru last month's chains.