I wouldn't consider myself an expert by any means but I'd like to add something if that's allright?
You have to take your training and then apply it under adrenal load and in scenario based situations. Practice awareness/avoidance skills. If they fail, what if the guy trying to pummel you is your father in law who's about to pay the deposit on you and your wife's new house? What if it happens in a narrow corridoor? What if it's dark?
You have to do this training at heavy or full contact and with realism. As we all know, people don't punch and stop like in traditional classes, their weight follows through the tchnique. If you're not ready for the follow up, your initial reaction doesn't matter.
You have to train against the attacks that you're actually likely to encounter. Straight punches in walking stance? Hmmmmmm....
This doesn't mean drilling technique vs technique, it means understanding the nature of the threat you're likely to face.
And the thing that woke me up the most is the way an attacker can go from nothing to sudden and murderous violence in an instant, and how shocking that is to most people. Dealing with that without caving in is the first obstacle for self defence.
Hope that makes sense
Mitch