It seems to be indisputable, in many of your minds, that the Bowline has a tendency to come loose. I see where you all are coming from, as I have never had a real issue with the bowline. However, I don't deny this is a factor. Rich's video demonstrates the well documented tendency of the bowline.
Just for interests sake I took three books off my shelf, four if you count "The Tree Climber's Companion" I have referred to before, and they support Rich's Warning. Again, Rich is not, I don't think, trying to ban the knot from use. He is simply demonstrating what has been said in the literature I have read.
The three/four books:
"The Fundamentals of General Tree Work"
'To lesson the problem of seizure from hard pulls, leave the top loop a little loose; in other words, don't form the knot too tightly."
- This one I included to show the thought of tying the knot looser rather than the jammed knot some have suggested.
"Arborists' Certification Study Guide"
'Not a good choice for attaching a climbing line to a carabiner or snap.
Backing up with a stopper knot recommended for some applications.'
"The Complete Book Of Knots"
'Neither a bend nor a hitch, the bowline (say 'boh-linn') is a knot that makes a fixed loop. It is far from the strongest loop knot, reducing the breaking strength of any stuff in which it is tied by as much as 40%. Nor is it very secure, particularly when the rope is stiff or slippery, when it has been known to capsize (if excessively loaded) or shake itself apart (when unloaded).'
"The Tree Climber's Companion"
"The Bowline does have a tendency to creep and potentially work loose, particularly in stiffer and slicker climbing lines. Therefore, it is strongly recommended that the Bowline be made more secure by using the Yosemite Tie Off, especially when used as a rope termination with the split-tail climbing system."
I am not saying anything about their credibility or anything, I am merely pointing out that it is a common trend that shows Rich had reason for sharing.
I still think the Bowline deserve its fame as the King of all knots, but it has its place!