actually in a real fight with others of the same caliber the most important thing is instinct and how well you adopt to the specific situation. YG overall lvl in correlated to the sad palm just like GJ to dragon palm.
HYS statement is flawed it's not accurate since he haven't exchange palms with GJ in a long time and thus don't know how much he have improved and also he didn't trade palms with YG potentially output which would overwhelm him.
The truth being said, the fact is that YG is the only great to defeat another great in the triology. Based on this fact we can say YG > other greats.