-The Best defense is a good offense
-The Best offense is a good defense
-The Best is a simultaneous offense/defense
-The Best way to get out of a Choke is to never get into one
-The Best way to take a punch is to not take it
-The Best way to get off the ground is to never go down
-The Best way to escape the mount is to not get mounted
-The Best counter to an armbar is to not get into one
-The Best way to Survive a fight is to not get into one in the first place
All seemingly simple statements, but most of the time they are not really addressed.Putting your opponent on the defensive can take away their offensive capabilities, but at the same time,if your defense is strong, it can allow you to impose your offense while thwarting theirs.Most people will sequence from offense to defense and not really integrate them simultaneously which is the best method. And even worse it their transition from one to the other is not fluid.
Anytime your attacking,you must not get tunnel vision where you don't see & are not prepared to react to a counter-attack.If/when they do launch a counter, the best way to deal with it is the incorporate an offensive movement with the defensive one or at least use a counter tactic yourself that leaves you in a more advantageous position(such as moving to the outside/blindspot,slipping a punch to set up you own,counter a shoot/off balance them while moving for a head kick etc.) The offense & defense can even happen at the same exact time or the offense becomes the defense as in a "stop-hit".
Many self-defense exponents will concentrate on getting out of various holds, but don't work on how to avoid them in the first place.If someone is shooting in to clinch or do a takedown,its much better to not allow them to ever get a hold of you in the first place.Don't just work on getting out of headlocks,chokes & the like, also work on that transition/movement when they are in motion to attain that position.This takes timing, control & usually footwork on your part. Fedor Emelianenko's greatest strength is his ability to anticipate his opponents movement before or immediately it has started and then flow & transition into the appropriate response & countermeasure.He reads the adversaries intent & intercepts before he can apply it.The same concept applies to the not getting into an altercation in the first.If your studying self-defense,then that indicates that your intent should not to get into a fight intentionally.You should spend just as much time learning de-escalation,body language & avoidance tactics as you do actual physical techniques.MMA fighters are "willing combatants",which can in no way be called "defense" since they put themselves into that situation.True self-defense is self-preservation and that is best accomplished by not fighting in the first place.