AV interfaces and :after redefinitions

[osiris@cs.utexas.edu (osiris)]

Two questions:

[1] Are there any MCL interfaces (or even C interfaces) for the AV machines
functions yet, especially the video stuff?

[2] Say I have a file that defines an after method.  Is there any way to
clear a previous definition for that after method so that reloading the
file that defines the after method will replace the old definition instead
of agumenting it?

--Thanks.