This was one of the really cool parts about getting the opportunity to drill these situations with simunition guns. You get the feeling of shooting a real gun and seeing where you hit, with both sides moving.
In the drill we did, the bad guy approached with a knife attack while your gun was concealed. We parried, blocked the knife attack, got off line, breaking their balance and then shoved them. After the shove, you had plenty of time to draw and step back. When they recovered their balance and started to turn back, it froze the bad guy momentarily. And it was predictable where he was going to be.
I found that this exercise validated the way I practice shooting at the range. I was easily able to to hit the bad guy where I wanted, one handed or two handed, depending on the distance I achieved during the first bit. (this was done point shooting, no one used or attempted to use the sights... most of the time, the gun was still kept close to the body, as you had to shoot fast)
I highly recommend that you try out these drills with simunition guns if you ever get the chance. We had two experienced SWAT team leaders teaching us and running the drills. This was the best gun disarming / situational shoot course I have taken. I learned a lot from it. If you can't get simunition guns, use airsoft guns. Its not quite the same... but closer than dummy pistols or water guns or nerf guns...