Rhinegold-
Hmmm, I just read most of this thread. I think I get the jist of it. Bear with me here a minute and I'll try to answer.
If I were going to just answer the question in the title of your thread, I would say "No, because it is not beneficial to the wood, and in fact, over time will be detrimental." Why? because of the stresses put on the wood, first one way, then the other. My belief is that it would continue to weaken the wood over time. The bow will lose draw weight, etc., etc. We've all been over that. What you have here in this forum, if you choose to listen to the right advice, are the voices of experience. We've all broken bows. We've all built bows that came in under weight, or poorly tillered. What we all have done along the way is learn to build better bows.
I have seen the video and other videos done by the aforementioned bowyer on the "tube" long before this thread was posted. Some of the things I've seen that guy do make me cringe, but I've never bashed him. He simply has much to learn yet, as do I. I wonder who gave him the idea that exercising his bow limb backwards would help? In my opinion, I believe it was more for the bow holder's benefit, than the bow's.
Dean Torges, who I regard as highest on my short list of grand master wood bowyers, will tell you straight up if you are doing something wrong. He'll also let you know when you've done something right. He has also learned to stay away from archery forums on the interweb.
That man, along with Gary Davis and others, past and present, have a vast wealth of knowledge stored in their heads, regarding bowyering, and working with wood. Thankfully, they have shared some knowledge with us (along with other bowyers) and sparked a revival of a once forgotten craft. I believe ol' Dean would also tell you to go right ahead and clamp your bows limbs to a brace every night, if you think it will work, just so you will learn from your own experience. He encourages the learning process. He has just given many of us a head start.
The key word in my reply is "experience". That said, I wish you many great experiences in life, and I'm looking forward to another glass of lemonade with Dano one day.