> > You could reduce this cost by narrowing the scope of the selector: > #parent a.tips, for example.
if you added this selector to the document body, it would still be just as
expensive as it would be run every time you moused over anything. This is
bad:
document.body.addEvent('mouseover:relay('#parent a.tips')', fn);
this is the much, much better thing to do:
$('parent').addEvent('mouseover:relay('a.tips', fn)
