I think it's worth noting that in the Lifestyles condom measurement study, which is pretty much the most unbiased (not self-measuring) study (IMHO), length measurement was done along the top while pressing the ruler against the pubic bone.
If the official LPSG methodology is measuring without pressing the pubic bone, that's more than fine, and it's good for the site to have a standard... but let's not pretend that it is the standard way to measure outside of this site.
There are some problems with either method. In the non-pressing method, on some people, an honest few mm's or maybe quarter inch or more can be missed, if they have some fat there. While fucking, I don't think that fat deposit would stop a thrusting motion... it would most likely be compressed a bit, afterall, we're talking fat and skin.
Now with the bone pressing method, there is always the question of how much or how little pressing is done. My pressing may be less or more than your pressing. If I want to use all of my strength and press in on my pubic bone, I can press hard enough to almost draw blood and get an extra 8th of an inch... while someone else may press lightly...
Also, if someone has a serious curve in their dick, I can't see a problem in trying to follow the curve. All of that length goes in the pussy (or ass if that's your thing :wink
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