I have read those threads but not entirely.
The general idea here is that the stretch does less than the regular stretch because the ligs aren’t involved. That is correct. The ligs are an important part of length gains but as you probably agree not the only reason of length gains. Also the tunica, CC and CS are important in length gains and (big) gains can be made with stretching them.
I believe this exercise gives a really good stretch at the centre of the penis. When performing this exercise I really feel a stretch at the centre. No exercise stretches the centre of the penis like this one. I don’t really care where my length gains are from and if I can make them at the centre of my penis, I will be as happy as when I make them in another part of my penis.
Of course you can state that by performing this exercise you waste time that you could use for stretching the ligs. When you want to make gains from the ligs that is correct. But in PE there are (girth) exercises like the Uli which does nothing for the base for the penis while horses don’t give you head and upper part penis gains. Still these are good exercises, which helped countless members reaching their girth goal. The two way stretch could do the same to countless people for length.
There are also members, mainly vets, who already have pulled their inner penis (partly) out. For them length gains should come from another area, the two way stretch could help them. Next to these people, there are also guys who have a big base girth, which according to many people, limits the gains they could make from stretching. Because the two way stretch doesn’t involve the base, they don’t have this problem.