Six metres is half a tennis court. That's a distance that I can easily run to get in position to hit a volley. Of course you can run that distance and stab someone as he takes his gun out, and if you are to counter that you must move too.

If you're rooted as a tree, of course you'll be killed. You must make use of your own movement to create time, just as Nadal does when he step diagonally back from the ball 'sal y entra'.