Pretty apparent I don't know what I'm talking about but is it possible to add a 2 or 3 cog cassette to a Rover with Nexus 8?
I'm still studying appropriate chain wheel for BBSHD equipped Rover tandem. Performance varies depending on whether my stoker/wife is pedaling or cruising (which is allowed ) or whether she is on board at all. Gear changes at the back end of the chain could help. I've done no math on this :-)