The only thing that would really make any sense, is that Photoshop Elements has some kind of Safari Extension installed or is attempting to use the Safari rendering engine for something.
Since you've ruled out the easy and pragmatic solutions, you get to go mucking about looking for the ties between the two programs, but based on a very cursory google search, it looks like this has been an ongoing issue for the past 3-4 years, so if it hasn't been worked out by now, I wouldn't go getting my hopes up of it ever being worked out.
My stats:
iMac OS X 10.5.8, 2 GB RAM, 162 GB available.
Safari 5.0.6
Photoshop Elements 10.0
Whenever I work with Elements (which is daily) and then go to Safari for whatever reason, Safari becomes unresponsive. I have found that force quitting Safari 2-3 times brings it back to normal operating speed. This works the same whether or not I quit out of Elements.
I like Safari and do not want to switch to Firefox or another browser. Is there a way to resolve this conflict?
TIA
P.S. Emptying Safari's cache does not help. That's the only thing I have tried so far.

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