We currently don't test for cases without mesh connectivity. And, we don't test for parallel (distributed) meshes.
Current tests: https://github.com/precice/precice/blob/develop/src/precice/tests/WatchPointTest.cpp

couping-scheme:multi is a rather complicated feature of preCICE for which we currently over no real example. Documentation entry.
To create one could be simple though: A channel flow with two flaps or two channel flows separated by an elastic membrane would do the job.
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