  Various local hidden variables models for the singlet correlations exploit
the detection loophole, or other loopholes connected with post-selection on
coincident arrival times. I consider the connection with a probabilistic
simulation technique called rejection-sampling, and pose some natural questions
concerning what can be achieved and what cannot be achieved with local (or
distributed) rejection sampling. In particular a new and more serious loophole,
which we call the coincidence loophole, is introduced.
