There are probably two reasons that you are getting a good stretch going down. You’re directly hitting the ligs rather than combining stress on tunica and ligs, and its easier to pull down as you can push with the whole arm and shoulder whereas simple upward stretches seem to mostly hit the forearm.
I think the curve along the shaft is not a major factor once you start stretching. You will probably gradualy effect the angle by stretching down if you are placing greater stress on the inside of the curve but how noticable that will be is another thing.
I think Bib’s LOT theory tells us a lot about what might be the most effective stretch. If your LOT is toward 12 you’ll probably make as much gains pulling straight down to effect the ligaments as you will with an inverted v-stretch, jai or a blaster where you’re effecting a combination of tunica and ligs. A standard v-stretch will cause greater stress on the ligs still. If you’re LOT is toward 6 you probably need to adopt the methods that attack the tunica more. The LOT is probably some kind of indicator of erection angle if you take out the effect of any bend outside of the body.
If you want to to an upward stretch and make it more effective try adopting some kind of inverted v approach, so that you can add the tension in a downward direction but have the effect of pulling in an upward direction from the base.
Lots of people also talk about taking a divide and conquer approach to the ligs, adding more stress to the left and then to the right so that you are pulling against something capable of resisting a lesser force.
Does that come anywhere close to touching on any of the points you were making?
