Re: "Internal" and "External"
I tend to agree with Chris on his point. The problem for me is that as terms used in martial arts external and internal are simply not helpful at all IMO. I avoid them when possible. I think that Mike Sigman's article for me does a good job of outlining how complex the discussion can get over describing the physicality of what is going on.
So, if there is a difference, I think Chris and I are arguing that the dicussion is alot more complex than simply using two words. and I agree with his assessment that on the paradigm that it is most often discussed by people who really don't understand the complexity of different types of movement it is done so in the context of "good" "bad" movement vice different physcialities
In the end if the goal is to move something, then the goal is to move something. It really doesn't matter how it is done as long as the goal is accomplished. If we use so-called internal ways or external ways...does it really matter...no not really as long as you can do it.
Now if we can't do something that matters like lifing a heavy weight or triggering a proprioception that matters...then it may indeed matter how and what we use. of course, that implies failure of some sort and now we have a baseline in which we can discuss efficiencies.
Outside of that, I think it is a moot point and when we use words like internal and external, we typically fail to establish a baseline of measure and people go around doing just what Chris is saying..."oh, that is a bad way to move 20 lbs of weight, you should be doing it internally".
I'm an advocate of "internal training" methods and I am a guy that ask "how do you do that?" and I am curious about using different ways of doing things that are seemingly better. Where I have always had issues with it is based on realitive value in a martial application where there is so much going on.
I do work hard to over come my slowing body and aging process which I see IS/IP stuff gives hope. However, again, internal/external....WTF does it mean in any real sense that provides us meaningful constructs?