What defines responsiveness?

I’m just wondering, i know it’s the response system. but does string and weight of the yo yo affect it? i had some just plain poly string on a mosquito and it was completely unresponsive, then it broke and i put some buddy jim string on it, that i had used on my DM and it was completely responsive even when i just threw a sleeper it’d come back up and destroy my hand o.o

and the opposit happened to my DM

The bearing, string, and response system all play parts into the responsiveness of the yo-yo.

Ok, I have never had the pleasure of using Buddy Jim’s string but as far as polys vs. _______, string thickness or type (as in type 6, type 9, type 10, etc.) can certainly affect the responsiveness of a yo-yo, especially with fixed gap throws. Now I don’t know if Buddy Jim’s is thicker, thinner, or the same thickness as the poly you were using but another contributing factor could be what material the string is made from, cotton seems (is?) more responsive, or grippy. For example, my Type 6 100% poly string is of normal thickness and USUALLY in a non-humid climate is slick and unresponsive. Whereas my Type 6 Slick 6 (50% Cotton/50% Poly Blend) string is noticeably more responsive and seems to cause more of a “sticky string” feel in the same climate with the same thickness.