You have two options. Double the length of your or your partner's cock, but half it's girth, or double the girth, but half it's length.
You may go beyond double, but you must reduce the latter to the same degree.

I, choose length.

Both.

The options negate eachother, resulting in the annihilation of the cock.

Tensile strength

Long and thin goes too far in.
Short and thick does the trick.

Uhhh uhh maybe girth? I wouldn’t want a 16inch cock, 4in and thick as fuck sounds manageable, not ideal but manageable

Girth because I don't want to have my cock to be concealed in ten steps.

1,000%

Ummm... both? ;P

Girth definitely impacts how it feels inside you the most, so halving the girth would suck pretty hard, so i guess we're halving the length and doubling the girth

I'm at just-above-average length and ridiculously above average girth already. Extremes in both respects put you at risk of hurting your partner while you're doing it, and I just recently learned that my thickness can already be too much for some. I'd rather not put that into the 'harmful to everyone' territory. At that point all you'd be able to do is... idk... be the object of worship in fertility rituals of certain cultures? And while that can certainly have an appeal of its own, if I can't do anything with anyBODY without harming them I'd rather just stay as I am.

Feeling stuffed is the best

My gf and I prefer girth

I'm a girth lover
The fatter the cock, the better.
If it's long, that's just a bonus

The people have spoken. Girth is the superior trait. For now.