Victor, this should also work for dictionaries as well.   Fundamentally, the concepts of loop-unrolling and exploiting cache locality should apply to any hash table implementation.

That said, the dicts are more complex than sets due to 1) storing the hash/key/value 2) key-sharing, and 3) different access patterns.  So, it will require more effort than just porting over the patch.  Feel free to open a new tracker item for that one.  It will take more work but will potentially have a much greater pay-off.