Great content!
I'm gonna share my strategy when BTC tanks like this:

Move altcoins for BTC right before the fall so you keep your portifolio stable in terms of bitcoin and surf up with it eventually,
Remember: surf it up and when it stabilizes the first altcoins to move up right after are Litecoin, BCH, Dash and so on.
After that go back to your former positions in other alts.

Doing this you'll freeze your BTC during the fall and get the run up when altcoins go up.