this topic has not mentioned the ooda loop. If you don't know what it is, do a search for john boyd ooda loop and fighter combat.
You can get the other guy disoriented enough by "acting" along with his plans and then changing direction radically. This will buy at most 2 seconds, maybe only a fraction of a second but you can get off the line of most guns. This is not a safe plan of action but you will most likely end up alive.
dropping your wallet while fumbling can cause the bad guys eyes to drop long enough for you to run, draw your weapon or grab his.
I am not going to use this unless I am pretty sure the guy will kill me anyways, but it does work in force on force with airsoft and rubber knives against trained assailants.
As mentioned, once you go on the offensive you cannot doubt yourself or stop until the threat is eliminated. This may mean you keep running or it may mean you have to draw a lot of blood. Poking eyes, ripping skin, getting shot, fighting thru pain. It ain't gonna be pretty at that point.
I have always adhered to the "no fair fight" adage. If I am using physical force, it is because physical force has already been used or threatened on me or mine. Not in retaliation for verbal insults.
And if someone has attacked or threatened me (6'4" 245#) they probably have some clue how to fight or are pretty darn big themselves.