Yes agreed. And horses can never be completely armored, they never had armor on their legs at all as far as I know.
Somehow the Polish Hussars were still pulling off cavalry charges into arquebusiers and musketeers as late as the 1680s, how exactly they did it is a mystery, a lot of it was apparently their formations, since as you imply there is no way to make cavalry completely bullet proof. But I can't seem to find out much about it.
Bottom line is though clearly if heavy cavalry is exposed to concentrated fire they are vulnerable to high-energy missiles, whether that's Longbows at Agincourt or Recurves at Leignitz or Arquebuses at Pavia, and no cavalry anywhere ever (at least until the Industrial Age) was safe against cannonfire. It's a separate issue from how effective armor was vis a vis hand guns. So I guess in one sense it doesn't matter I'd just like to know more about it.
BD
