just have to keep moving, nice large moves, and move you mouse every once in a while (like every 15 seconds - 30 seconds).
You can circle the block, which always works, or, you know sometimes in multi how usually all the players are like top left of a block and killing the boss in that open area there, and they are just making a circle basically or like moving randomly in that small corner of the block. It's just to imitate that same movement, use all arrows, up, down, left, right, up left, up right, down left, down right. anytime you want to rest just press esc to pause.
And as everybody else has said, the zombie well more boss freeze is the one the one to look out for. Better to use the dza that doesn't freeze the enemies.
and of course, they are able to tell is player pressing keys, (like was o presses, was e pressed, screen mouse position) etc, which keys you press, so, even though a boss is pushing you around but not attacking and you don't need to move (cause basically the boss is moving you all around the place), you still have to press some keys to mimic that you're playing, that's all your really doing, mimicking that you're actually playing.
just think about how you would play in real life and mimic that. then eventually you could record a nice long script, play on auto. I haven't grinded in years, everything auto.
Sometimes, if you've ever played with a uwc or ugau for ex, and in multi, you don't really need to move, sometimes I'd just stay right there, standing still, killing everything, only thing you need to move is your mouse, you won't get exp after about 2 minutes of standing still but, it's still legit playing, because of all the drugs and speed boost and damage boost and implants, and power creep of weapons, the threshold of max damage and max speed max incoming damage reduction etc. always increases. that's all you have to do, imitate what you would do if you were playing in real, quite fun actually
The most beautiful thing though, is to run many tests. I love running tests, it's like a science project. test all different kind of things you can think of.
I like getting a ban, cause then you learn something. If you learn something everyday, et the end of the year you'll be a genius
super sprint, is fine.