if the method is called "f" and it exists on "a" then you have access to "f" via "a.f()". It's redundant to call it via "f(a)". If you're saying it's easier to

if the method is called "f" and it exists on "a" then you have access to "f" via "a.f()". It's redundant to call it via "f(a)". If you're saying it's easier to edit "f" in the repl/notebook vs. on the class where it's defined, well that's a sort of a convenience factor, I wouldn't exactly call it a huge benefit overall as this is mostly a very specific use case.