So you mean if we reach this state of girthier semi we could keep going and in the end longitudinal fibers would accomodate?
It could also suggest cycling through length work even though we work on girth could be helpful.
I think the latter option would allow for quicker results.
You could see it in an other manner, if the outer layer is more elastic the inner layer may push it easier in a semi erect state. Once erect, the outer layer becomes much less pliable anyway.
I think bundled stretches should work both circular and longitudinal fibers.