@sferik -- I'll probably formally request it once I start using rubocop.  I feel weird making a feature request to a project I haven't tried to use yet.

@yujinakayama -- it makes sense to me that rubocop wouldn't enforce `__send__` over `send` by default, but for  libraries like RSpec, I think it would be useful.  I'd be fine with it enforcing it statically (e.g. not allowing `send` at all, even for classes that define it) since we won't ever define it as a method on anything and always want `__send__` to be used.