This has indeed been an eye-opening thread. Definitely has me rethinking my cavalier approach before the next HD backup takes place!
FYI - Got a response from Jonathan P. He's too busy to contribute, but asked me to pass along an illustrative anecdote-
I installed the Safely Remove USB utility on my computer last week and am using it happily. I like it so far. But I have not tried any other similar utilities.
I can report that I trashed a USB flash disk last year by pulling it out AFTER trying the MS Safely Remove Hardware icon (didn't respond) and then waiting a while to make sure any files were done copying and the light was not flashing. It got ruined anyway. So I do recommend utilities that can help prevent this.