glacier-cli calls its own command glacier rather than glacier-cli or something else. This conflicts with boto's own glacier executable, as noted here:

Whilst the glacier-cli project should resolve this conflict, it would be good if git-annex could be made to use a configurable path for this executable, rather than just assuming that it has been installed as glacier. After all, its installation procedure is simply telling the user to run ln -s, so there's no reason why the user couldn't make the target of this command ~/bin/glacier-cli rather than ~/bin/glacier - it's really irrelevant what the source file inside the git repo is called.

Of course, checkSaneGlacierCommand is still very much worth having, for safety.