>  before trying to change ruby, try first to understand it.

Before we start calling each other names, I need a clarification. I can do
this in Ruby:

  class A
  end

  class B < A
    def m
      <some code>
    end
  end

  class A
    def m
      <some code>
    end
  end

Where <some code> twice represents the same bit of Ruby code. Nobody can
keep me from doing the above. If I understand correctly, Ruby doesn't
allow the method to be copied from B to A, only from A to B. Now the
reason you say that Ruby's test is correct, and it rightfully prevents us
from copying a method from B to A, is that because the above Ruby code
doesn't make sense, or because Ruby somehow internally fixes method m for
use in B such that it is no longer fit to be used in A? Or rephrased, is
it because moving the code is wrong at the Ruby level, or at the
underlying implementation level?

Peter