> So you get the best of both worlds and randomization would only
> kick in when it's really needed to keep the application running.

Of course, but then the collision counting approach loses its main
advantage over randomized hashing: smaller patch, easier to backport.
If you need to handle a potential abnormal number of collisions
anyway, why not account for it upfront, instead of drastically
complexifying the algorithm? While larger, the randomization is
conceptually simpler.

The only argument in favor the collision counting is that it will not
break applications relying on dict order: it has been argued several
times that such applications are already broken, but that's of course
not an easy decision to make, especially for stable versions...