Is it possible to get mixed content repositories working in conjunction with a directory special remote using importtree/exporttree?

git annex add adheres to the annex.largefiles setting (mimetype=text/*), but importing or syncing from the remote invariably adds text files to the annex, including if the file was originally added to git and then modified on the remote.

I want annex.synccontent set to true but have tried it both ways.

What am I missing?