In its current state we miss at least two test cases, to ensure the
protection against faulty clients is fully functional:

1. We need a test to cover a faulty client at 'readPinWatchers':
   currently we only check if faulty clients are killed which
   are already faulty at the initial watch request.

2. We need to test if a sane client get really the data served
   in combination with a faulty client that's blocking.

This patch adds TODOs for these two extensions.