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+Resuming interrupted uploads to encrypted special remotes is not currently
+possible, because gpg does not produce consistent output. Special remotes
+that could support resuming include rsync and glacier.
+
+Without consistent output, git-annex would need to locally cache the encrypted
+file, and reuse that cache when resuming an upload. This would make
+encrypted uploads more expensive in terms of both file IO and disk space
+used. 
+
+[It would be possible to write to the cache at the same time the special
+remote is being fed data, and if the special remote upload fails, continue
+writing the rest of the file. That would avoid half the overhead, since
+the file would not need to be read from, just written to. (Although OS
+caching may accomplish the same thing.)]
+
+Also, `git annex unused` would need to show temp files for uploads,
+the same as it currently shows temp files for downloads, and users would
+sometimes need to manually dropunused old uploads, that never completed.
+
+The question, then, is whether resuming uploads is useful enough to add
+this overhead and user-visible complexity.
+--[[Joey]]