I've been checking this a bit more and my conclusion is that it is definitely
possible to provide thread-safety for libraries that are not safe out of the
box while still allowing thread-safe ones to make use of connection pools.
Now the bad news is that none of the two blessed memcached librari
I believe I'm (at least partly) responsible for this change, and the short
answer is basically "historically memcache client libs have been awful with
threading".
This may have improved, but in order to avoid a whole slew of potential
problems (with memcache and other backbends) I copied the pa
