I don't believe one can apply the same 'math' to the two different technologies. Resolution of a film scan is just not the same as resolution of a digital camera file. About the only similarity i find is the point where one starts to see pixels upon enlargement, but even that has variables. As well, digital files can be more easily up-rezzed before seeing artifacts.
Forgetting the science - my digital files are ALWAYS perceptibly sharper than my film scans, whether they be from 35mm or 6x6/6x7 film. They're also 'cleaner.'
More importantly, unless you're shooting only stills (landscapes, still lives), with a tripod and the absolute finest-grained film, it's all moot anyway. At 'real life' ISOs, at least for me, film grain gets in the way and i don't shoot anything above ISO 400 color film. I'm going to try Fuji's 800, but i know what to expect. With digital, though, i can go up to ISO 1600 and still get cleaner results than with ISO 400 120 film.
I'm certainly not saying digital is "better," though. I still prefer the look of film, and it has nothing to do with statistical measures of "tonality." One can always still insist upon the superiority of film, but just not with these kinds of figures.