How are memory classes different from one another?

I'm confused as to how creating memory classes yourself will help when it comes to detection. Considering most memory classes run off of the same mechanics (ie stuff like rpm and wpm) wouldn't they all be easily detected? Aside from slight differences like variable names. Or is that enough to make it undetected?

Could someone provide some clarity on this subject?

Variable names are not compiled into the program, so changing those wouldn't do much. If they work by pattern scanning for larger portions of code then changing the order or layout of the code could be enough to break the pattern.

You can write your own methods for rpm and wpm and be more undetected.