Jumping in late here with some random comments.
Tom House is the one credited with having invented the towel drill. But most of what you see people teaching/practicing with the towel drill (extension, snapping down, etc.) is
not what House teaches. While House does believe in a release point that is out in front, he doesn't pursue it by practicing "extension" using the towel drill. House uses the towel drill to teach total body mechanics. If you do things properly (i.e. no lunging, etc.) then the only way to hit the target with the towel is to "put it all together". In other words, you've got to maintain good balance and posture, you've got to manage the glove side to allow yourself to stay closed and rotate late, and you've got to generate good momentum. Release point happens as a result of all of these things. Really, trying to "extend" and change your release point just doesn't work when you're moving full speed and the arm is rotating at 7200 rpm.
I don't have my pitchers do the towel drill on a regular basis but I will use it when I have a pitcher that needs to work on making a particular mechanical adjustment. It lets them focus on their mechanics without being distracted by throwing a ball.
Dick Mills is a competitor of House and he loves to bash House - you see it on his website. (Very classless in my opinion.) Part of Mills' attack on the towel drill is really an attack on all of the incorrect teaches using the drill. But I'm sure he has no problem using it as a bash on House as well.
The pitcher in those videos posted above does not do things the way House would teach. That pitcher pulls his glove and is late in moving his center of gravity forward which goes against what House teaches. Also, the cross-over version of the towel drill is designed to promote early forward movement but the pitcher in the video uses a very deliberate up-down-out movement of the stride leg and doesn't really start forward until the leg starts out. These things would work to prevent one from hitting the target with the towel at the target distance. Seeing this does make me wonder what the focus was for that pitcher in doing the drill. It looks like he was focusing on balance point and planting on the front part of the stride foot.
Regarding using video vs. seeing things with the naked eye, knowledgeable coaches know what things to look for and that helps them see things. Experienced coaches have trained their eyes to see things. But there are still times - sometimes with certain pitchers - when video is still necessary. And I agree with the poster above that, while any video is better than none, 30 fps is lacking and 300 fps is good. (I also have the EX-F1 camera.
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Finally, as far as the towel drill programming a flaw into your delivery is concerned, the same can be said for any drill.
Practice makes permanent!! Drill work should be supervised by a knowledgeable coach when possible.