DAR and FF
Actually FF I think it was a good post but for a different reason.
It brings home the key point on an interesting and very old debate.
For commercial ops it can be assumed that all pilots will perform to a given standard. In short a limit can be imposed because there is a reasonable possibility you will bend it if you go beyond the limit.
In GA the product liability lawyers learnt long ago that many of their customers really havent got a clue what they are doing. Consequently they are not going to tell you what the limit is, becasue many will try it and regret they did. However, what they will tell you is what a reasonably ham fisted pilot is likely to be able to get away with.
So as my final contribution on this one, I think how the number is derived is well known (to those on here at any rate), and I have seen absolutely nothing to convince me that it is in any way intended to be a limit.
(Sorry to disappoint you DFC - I respect the points you have made, I just dont agree with them)