When there's no voltage involved (like with a dynamic mic into a line input that doesn't even provide phantom power), I don't see what's the problem.
It's basically the same thing as plugging a dynamic microphone into a mixer, which you so advise. They both involve 0 volts.
I know I personally turn off phantom when plugging in mic (I'm a graduate student and can't afford any problems)...
What I'm wondering is where you got the hint in either of the first two posts in this thread that there was any sort of hotplugging involved? That's a totally separate issue from what he was asking about. What he's asking about, it's just like plugging a mic into a line input...does it work? Maybe barely, and if the line amp provides for it, it will be audible, but it's certainly not typical or adequate compared to a very cheap standard mic preamp solution.