I appreciate all the feedback!
1. I don't have to lean forward and then hyperextend my neck, pinching off my cervical cord, and I get to see what's in front of me rather then getting up-front-and-personal with my front tire. I don't know why I didn't do this years ago.
2. No reason the stresses on the handlebar clamp are any different from a shorter quill. In fact, maybe even less since Im not leaning on it. It's firmly clamped and isn't going to rotate. That's a solid alloy stem and isn't going to break off.
3. Yes, some of the cables were too short doing this and I had to replace them. Those were 6 mm OD cable housings with 2 mm inner cables. No longer off-the-shelf items, but for a few bucks I found NOS OEM replacements on ebay, so everything matches
4. Great observation about the similarity with a Russian bear riding a bike! There's a Great Pyrenees in the neighborhood that's about a big as a bear....we'll see if she can ride this.