1. I never allow anyone behind me and keep conscious of anything behind me...... at check out stands, I stand with my back to the racks, etc. and turned sideways ... so no one is to my back. I never sit with my back to anything other than a wall at a restaurant, etc. But, that isn't due to conceal carrying, it's due to the job I used to do .... LOL
2. Learned some judo, boxing, and also took Taekwondo for a long time.
There are many ways to cause people pain or serious injury ..... my suggestion is to learn some.
I have trained my kids, and have been training my grandkids. One day when a big HS football player (who liked to grab girls inappropriately, etc. & kept have encounters with my granddaughter) came up and grabbed her from behind (bear hug) and then began putting his hands in areas that were unwelcomed as well, he learned the hard way. He assumed he could over-power her..... since he is way bigger, heavier and much stronger by any means. She put him into a hold I had showed her, and then used another to ram his head into a locker.... making him unconscious for a few minutes, and later he had to go to the hospital for a brain concussion.
The Principle wanted to kick her out of school (a real idiot) , changing her mind..... when several students and numerous teachers who had witnessed it ..... went down there and stood up for her (about turned it into a full blown protest would be a better description), and saying she was attacked and only defended herself.... and how this guy had done the same thing to way tooooooo many other females. He got suspended .... came back to school, did something similar to another girl and was then expelled.
Also.... a good little knife inside your pocket that you can get to in such situations .... can be very useful in such situations.
If it's a rapist or an armed robber...... being able to get your gun and shooting them, also works .
Both arms...... straight up in air, and dropping all of your weight downward (free fall) will typically get you free from many holds.
There is another hold, that if you can even put your hand on theirs....... lol..... it's a hold/spot that will have them on the floor crying like a baby and doing anything you want them to.
Those who have ever told me that "wouldn't do that" ... have gotten a demonstration and were true believers after that.
It's just a matter of knowing them.
Ask my daughter if they work... she's 5'2" - 5'3", and when she was grabbed late at night by a 6'1" guy (with a long rap sheet of rapes) from behind when she was getting into her car...................
When Police arrived, they saw a lot of blood ... and it was all his. The guy was on the ground pleading for them to protect him and refusing to get up until they got her well away from him. They had to call an ambulance to take him to the hospital. When she called me and the Police officer got on to tell me what was going on, I could hear the guy screaming in the background, and the Police officer could hardly talk because he was laughing so hard.
Well done on training the kids and grandkids! That is so important and they never know when they will need it. My sister has a great story about getting a call from the school asking, "Who's uncle Hoganbeg?"
The thing is, these techniques aren't that hard or take all that much training to do, if learned correctly. You hit the nail on the head: "...learn some"!
Your two best courses of action is to avoid having someone come up behind you unannounced and grab you. Working on a heightened situational awareness is what's required for that.
Your next best course of action should that actually happen to you is to learn the defensive techniques it takes to escape from such a grab and then immediately counter-attack, or gain distance before going for your gun.
The type of attack you described is relatively easy to escape from. But you have to take the time to learn some basic self defense techniques.
Using your gun during a scuffle where someone is all over you like a monkey on a cupcake is an iffy proposition at best. It is extremely dangerous and you are greatly at risk of being the one shot, or you get shot also. Going for the gun in that type of scuffle is a last ditch effort where you simply do your best and hope it works out.
You should be practicing and learning a lot more other things before you start worrying about how to go for your gun during that type of scenario. That is, if you want to survive it.