See
http://www.teddytactical.com/SharpenBladeArticle/4_States of Awareness.htm
An important point about Situational Awareness is that you don't let people get the drop on you. Or more precisely, you work very hard to prevent that.
Diggers said:
It takes the average person 1.5 seconds to react to and unexpected event and in a store you expect people to come through the door so that will slow you down even more.
What condition they were in seem irrelevant to me. Unless they were standing there with a gun aimed at the door knowing someone was about to charge in there was nothing they could have done
Diggers has part of the answer that I am trying to explain on this thread. This is Strategy & Tactics. So I am trying to explain what strategy & tactics would help you in this type of problem.
If the criminals get to start you will lose, but if you start with hand on gun, draw to fire times starting with hand on gun are for practical purpose as fast as shoot time from low ready, you can shoot about as fast as they can.
Going to grip on gun can be done discretely so you don't scare people.
You can also do things so people can't rush up to you in less than a second or two.
I will outline how I would handle their security situation if I owned the store or they asked me for advice.
First I would control the entry point, this could be as simple as having to enter through two doors. Set the inside door to open outwards and the outside door to open inwards.
Spaced so you have to close outside door to open inside one. That would slow people down even without a lock. This should buy you at least a few seconds.
Ideally you would have buzzer on both doors and a panic lock button. So you can lock inside door like electric locks on a car door.
You can also just adjust the door closures (the mechanism that pulls door shut) so they are hard to open, and don't open all the way.
Second I would mount real or dummy camera inside so that it covers entry with a decal that says something like "This business is under 24 hour Video surveillance by ACME Security Corp". This might deter some and would make any would be robber more nervous and time pressured if they tried to rob the store.
This adds time and mindset to my side. Stress makes it harder to function, and even if they do attack and win, they won't want to stay long if they think the store is under surveillance.
Third I would be in condition orange, anyone that came near the door would be considered a potential threat. Which means I would be ready for them to start an attack. That greatly reduces the "surprise" factor.
I would be watching the door constantly since that would be the main point of attack. Also would arrange things so people outside the store couldn't tell were I was in the store or how many people were in the store.
In addition I would have at least a couple of prepared spots to fight from that provide cover for me, and those spots are were I would be when people entered.
I would also arrange items so people entering were in a funnel to limit their mobility. That will also limit the advantage they would get from having multiple robbers.
Everyone that entered the store would be greeted by me verbally while making full eye contact. That will make customers happy. But it will make criminals scouting very uncomfortable. They don't like people being aware.
Plus many convicts have a hard time not trying to stare down people that make direct eye contact with them. That would be a warning sign.
I would also be very careful when arriving at the store and when I left since those would be good times for someone to attack.
That is a very basic outline of how I would set it up solo. With a partner you can much much more.
To me the strategy is planning ahead to remove as many of the criminals advantages as you can, while giving yourself as many advantages as possible.
Doing that does a lot to make you seem like more than a criminal wants to handle.
These general ideas are ones I have used myself. So far with the advantages that planning and preparing ahead of time combined with staying aware and alert have given me I have never needed to draw my gun.
I hope it continues to work that way in the future.
But there have been several times were I had my hand in a pocket gripping a gun without anyone being able to tell that I was ready to draw.