I had a Concorde frameset a few years back that came set up with a Mavic tapered BB. While mocking up various build options on it I was still able to install a normal BB with plenty of thread engagement. I even seem to remember seeing online instructions somewhere for the BB mentioning that you could still run a normal BB after tapering the BB shell but don't quote me on that.
Sourced a Mavic Starfish crank in the end as I liked the look on this bike.