Thank you all for your replies..I know what many of you are talking about. "You can't draw fast enough to make up for a miss."
Some years back, I had just purchased a Colt SS GM...I had read in some gun mags about carrying the pistol stuffed in your waistband...sans holster. One night, I was in an OK area having an early evening dinner with my wife and 5 year old daughter at a restaurant. The parking lot was well lit but in the back of the restaurant, you had to go out the front door and down this landscaped (Lotsa bushes)sidewalk between two buildings and the walkway which wasn't well lit to get to the parking lot. When we got within 15 feet of reaching the parking lot a car came barreling up to the end of the walkway, a young man jumped out of the passenger side with something nice and shiny in his hand. I stepped sideways away from that hand and in front of my family, drawing the GM from under a light jacket at the same time. The young man skidded to a stop and raised his hands up as my hand came up and snicked the safety off.
He said, "Whoa!" and something metallic hit the concrete (later proved to be a steak knife...maybe he wanted to stop for a fast bite to eat?) He turned while still in motion and hopped back into the car as it kept moving out of the parking lot. I believe that time was one of my fastest draws.
I am not yet a competition shooter, but I do practice drawing and dry firing a lot. At the range, since they don't let us draw from a holster, I hold the weapon at low ready or I put it down on the counter with the weapon pointed downrange in my shooting bay and "draw and fire." Please keep the answers coming, as I am still experimenting with "rigs."