Can extension methods be overriden?

[Stephen Colebourne]

2009/12/14 Paulo Levi <i30817 at gmail.com>:
> Many times, while using the public methods of a interface is possible to
> implement a feature, using it efficiently requires using internal structures
> of the implementation class.

I'd like it to be a goal to permit a class to "implement" an extension
method more efficiently than the default implementation. However, I
haven't considered how this could be achieved or even if its possible.

Stephen