Patch Set 1: Do not submit

Aside from my less-than-usual descriptive commit message (sorry, baby started crying and I had to attend to that... I only found 15 minutes today for coding and this was it)... I've realized this probably isn't going to be a complete solution to Robin's commit performance problem.  So I'm yet not convinced we should commit this.  See the mailing list thread "Avoiding stat calls (again)" for more discussion.