This example tries to show how we could enhance the panning performance.
In this page, the map div is encapsulated in a complex inheritance (several ancestors), and it seems to slow down the panning because of the OpenLayers.Events.getMousePosition implementation. This example tries to demonstrate that with a different implementation, we could gain a lot.
To see this, you can drag the map around, then click on the button below, drag the map again and see the difference.