Im bad at csgo due to the fact I didnt like the style technically its your wanting and style to play and master the game, and some weebs are shit at games. The game I use to practice reaction would be hotline miami 1 and 2 using it is useful for me later in other games other then that in some way I could agree with you.
you well go for the head if you do mutiple shots then you can break the sheild knowing it has 60 health, if you do then you can get a headshot so its luck and timing. I dont play blackbeard nor have I fought much people playing blackbeard
Unless your echo you cant stop it, what you do want to do is take cover depending on the situation and try to get rid of the ring as quick as you can, in the safest area unless the enemy already knows your location