Barrel length relationship with the same other factors

Hello I have one more can say the last question - How is the "situation" with a polygon barrel and a fully cut barrel?

Obviously, with a fully grooved barrel, the position of slugs would be better for turning the "bullets", although the twist rate will also matter?

Regarding a polygon barrel - I do not have enough information about how "things" stand besides what she looks like visually ...

Greetings and thanks to all the colleagues who were so good to help me!