Campy already copied the slant idea. I have one of these.

http://velobase.com/ViewSingleCompon...d-b2a3cf313619

I keep it because it is art but to be honest a cheap shimano works better - I never had any problem shifting this but a lot of folks hated it. It really needs to work with a downtube shifter though for the "feel" as their is some technique involved.

Either way - you need the long cage to take up the chain anyway. The NR worked perfectly fine on a straight block - it was not intended for wide gearing. Why would it need to "shift better"?

Anway that site has some other versions where Campy tried several approaches.