Andrew ... I'm curious, have you experimented with the quicker permissions check function that the unified LASD provided us?
Minimizing the calls to permission_p is undoubtably important, of course, but I think we've sped up the permissions checking considerably from ACS 4 classic. A best-of-both-worlds scenario with file-storage, I should hope.
We should also just get rid of the file sort key in the postgres version. We already have the tree_sortkey and it's sufficient and it's already being maintained by triggers on the content repository. fs_order_files could be a NOP for the PG version.
