Time-to-load posted in the footer of every page.

Although it would be hard to come up with a 100% definitive measurement, due to query fields and post-processing, an initial time-to-load posted in the footer would help users to diagnose whether slowness is a result of an intensive query or network congestion.  If this were added as part of the event logs, it might even be possible for a client to graph the performance of a page over time (divided by talent group, physical user location, etc.).