The argument I gave was not about choosing two ‘linear’ measurements, but the volume measurement that accompanied them.
But, taking your argument,
The man can always help the woman get more feeling girthwise by having his legs outside the womans and pressing her legs together, but apart from different positions, there is not much that can be done by getting further in her.
I don’t know the full answer to that but I suppose it depends on what the woman prefers,.
But returning to my argument, the volume doesn’t tell her or anyone, anything about the actual length or girth.
So my discusssion remains - what is the point of a volume calculation?