> FWIW, I asked Ned Batchelder about this and he said this approach ("fullcoverage" [1]) was added to support running coverage on the stdlib. [...]

The docs you pointed out in [3] (where it talks about a *horrible hack you should never use" :-) should be amended with something explaining that "you need to comment out the line "<encodings.*>" from frozen_module.py for this to work, else the frozen version of the encodings module will take priority over the imposter from "fullcoverage"."