We don't have to look far to find a weird versioning scheme that can't
be represented without epochs: our largest competitor in the field of
general-purpose operating systems has such a versioning scheme. Imagine
we had a package that followed the same versioning scheme as Windows (I
could imagine a parallel universe in which Wine used the version number
of the version of Windows that it claims to emulate). If we packaged
that, using the "marketing version" wherever it's numeric or making up
something reasonable wherever it isn't, we might have had a versioning
scheme like this: