Rick, if you reread your post, you should be able to find the issue. You basically implied that tapping the wing hold down blocks is going to lead to failure due to smoothed over threads. Flyboy was probably not the only one to take issue, but perhaps just one of the few to comment. I learned this method at least 25 years ago, I've used a tap to make threads in many hold down blocks and I too have never encountered the smoothing over that you imply will happen.

In fact, in thinking through tapping the blocks versus over boring and using blind nuts, I think drilling and tapping is far superior. The reason I feel this way is since the threads in the tapped block are much closer to the wing, there's significantly less bolt between the head and start of the threads. Since nylon is known to stretch, it seems this would be a good thing. The taping method also eliminates any possible play that the over-sized hole needed for blind nuts would allow. I have used blind nuts for a few wing hold downs, but when I do so I use a metal bolt instead of nylon.