I remember tracing entire clone process. It was hanging in a function (don't remember which, the only one has fsync) what ensures sha key is in fs. I bypassed it with a rare mess, so if key is there, it works, if not, fails. In fact fsync changes introduced by Linus was in the line of ensuring that key is there to decompress package.
Maybe I was wrong. When I'll back to port git for Harvey, I'll see.

Álvaro