Today I found a nasty Safari 4.0 bug. By accident, I ended up with a css line as follows:
.orange {color: !important;}
The result is… Safari skips the complete rest of the css file after this statement. Took me ages to figure this out. But if this is persistant in some Safari versions, it might come in handy to make a Safari-Hack, like:
.dummy {color: !important;} /* rest of file is ignored by Safari */
So every disadvantage has it advantages.