FWIW, I’ve applied the patch at http://gist.github.com/123525 to my system, which takes care of the slowdowns for me. Of course you should backup the path_helper script beforehand, patching system scripts is generally not a good idea, use at your own risk and so on.
Interesting. I didn't know that one. But why do I receive an egrep not found each time I start a bash after having applied this patch?
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