Of course the penis is not muscle.
10x7 is probably the exceptional limit that can be reached in a erect able working penis.
Some guys, even with PE, grow slow.
Not all penis pullers get equal results and reasons are almost impossible to ascertain because each guy pulls his penis his way.
There are 2 beliefs:
1.you got what you have, penis size can’t be changed
2.penis size can be increased with PE.
Within 2. The question is how much? The “rule” of is probably a gain of 2” length and 1” girth.
Consider a guy who starts at 7.75”x 5.75” and gains in terms of above ending at 9.75”x6.75”.
Being on the closer side of 10x7 makes gaining anymore a mammoth task in terms of work put in for the simple reason that 10x7 is probably the upper limit of possible growth.
Consider a guy starting as a statistical average at 5.5”x 4.5” and him with PE gains a size of 7.5”x5.5.There is still room to get more, maybe not easily but probably more likely than the 9.75x 6.75 guy who is just about maxed out.
Anyway no can prove that the potential for more gained size is bigger when starting with a smaller size cock.
PE is fascinating and in the 16 months of PE I’ve gained 1 7/8 ” in length and 7/8” in girth.
I expect gains to come slower but there is still room before hitting the maximum wall of 10x7.
The possibility of another inch is not as “impossible” than for the guy on 9.75x 6.75 to get even half an inch.
Anyway I ain’t stopping PE and will soldier on.
Longer, thicker, tighter, deeper