Net"Snail" - how much is due to client?

I recently attended an Oracle seminar where the topic of discussion was around performance optimising their browser-based application.
There were a few interesting points that came out of the discussion which I thought I would post here to get some feedback from user experience as well as perhaps recommendations or suggestions from NS.  I realise this was about their specific application, but I would assume (and yes that may be the wrong thing to do) that browser applications likely have the same fundamental issues with performance.

1 - Client hardware matters.  The same browser running on very different hardware platforms can refresh screens at incredibly different rates.  In their benchmark, a P4/1Gb outperformed a P3/512mb three times faster (7 sec vs 22 sec)