Bumping this old thread, due to new information from the 2.2 patch notes.

The following issues have been addressed.
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An issue wherein the Fisher can obtain the Timeworn Leather/Goatskin/Toadskin/Boarskin/Peisteskin Maps even though their level does not fulfill the requirements.
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It looks like low-level fishers will no longer be able to collect maps from high-level fishing holes. Oh, well!