I was just looking at this actually. I think it will be a very useful addition.
As far as I can see, the following would be needed:
- move the master products fields from the products table into separate 1:N lookup table.
- rewrite the code in the admin and front end to use this new table instead
- as products will be able to have multiple masters a new section will be needed to assign products to a master products, rather than it being done in the child screen.
any comments or takers?? :)