Solving patch series collisions with domains?

[Vincent Povirk (they/them)]

>   As I read it, the issue here is not about determining the sender/author/...
> but rather that multiple patch series from the _same_ person, each with
> the _same_ number of patches can be confused.  The 'domain' is a
> proposal for an _additional_ way of distinguishing them.

Why isn't temporal difference enough in this case? Did the series interleave?