I don't have any specific knowledge of modern BBs, but bearing relationships are bearing relationships, and from free ball bearings in an old-style hub to the needle bearings in a motorcycle steering stem, they're all checked the same way. The part should move freely but without any play outside the intended plane of travel - just as you describe.

It's not a big deal to either hold the chain aside to check your BB, or to just do it routinely when you replace the chain.