So Lynn Thompson, chief owner and bottle washer of "Cold Steel Knives" has a blog and posted a video with some training tricks. MadOgre, the "blogfather" himself commented on how utterly stupid some of the advice shown on the video located here: http://blog.lynncthompson.com/2011/08/glock.html
I'm not a professional firearms instructor (although Ogre is), nor do I play one on TV (or YouTube). I am however well trained in training riflemen for the US Army although it is not my primary function. My primary function is to ensure that my NCOs are proficient at training marksmanship (and usually they are, but sometimes they too need corrective training).
As far as Lynn's level of fitness, that is his issue. I've seen morbidly obese service members from every branch. The good thing about having a gun is that it kind of negates the advantage the other guys has in how many pushups he can do every morning.
The idea of "suppressive fire" is simple. Shoot to make the other guy keep his head down while your buddy flanks left (or sometimes right, we mix it up like that cause we can) who can then take a kill shot so you can move on to the next objective and do it all over again. This is a war zone tactic that is the very basis for "fire and maneuver" which means a STATIONARY base of fire and a MANEUVER element flanking. It ain't rocket surgery. Some people think "fire and maneuver" means shooting on the move, but that is not the case. You will shoot and move for CQB, but I don't care how good you get, you will never be as accurate or as effective as when you are stationary. Practice enough and you can get pretty darn good, and at pistol ranges that is "good enough for government work."
Now, at NO POINT IN ANY CIVILIAN SITUATION should you use "Fire and Maneuver" to "reduce a threat" because simply put you are not at war. If you are at war please disregard and go about your business. If you are a law enforcement officer and the Zeta's come to town, hit me up and I'll give you some good pointers on how to use fire and maneuver (and hopefully dedicated marksmen) to keep you from becoming another decapitated corpse hanging from a bridge.
However, if you aren't fighting off a ruthless Mexican Drug Cartel you probably don't have any reason to practice "fire and maneuver" or "suppressive fire" when defending your life or the lives of others. Shoot to stop the threat. If that means "shoot to kill" that is what you do. Don't shoot the dirt, don't shoot to warn, shoot to stop the threat.
I have seen Navy SEALs use the "stitch" technique to clear corners. It is like "pieing" the corners except you are pulling the trigger the whole time to keep whoever is on the other side of the corner from being able to pull their trigger back at you. This works when you have a lot of men with MP5's and plenty of ammo. It doesn't work when you have a 5 shot 38 Special revolver as your carry piece. And that extended mag on Lynn's Glock? Probably not something you are going to carry day in and day out unless you happen to by Jared Loughner....
Aim fast, shoot fast. Don't spray and pray. Don't "walk your rounds in" unless your rounds are coming from long distance assistance in the form of mortars or artillery. Remember that you are fighting to stop the threat, not kill Osama Bin Laden on a night raid in a foreign country.