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Posted: Wed Jun 15, 2011 11:15 pm
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Even if they don't ask for it you can still upload it and submit it when you submit your application.
I would separate the PS and DS so that you can zero in on the topic instead of trying to figure out how to weave it all together. If the PS deals with diversity of some sort then you should probably mention it and then go into more detail on your DS (just make sure you don't repeat what you already said)
If the school doesn't ask for a DS then you can save it for later in case you get WL or they are taking too long so that you can send it to show interest along side a LOCI
Hope that helps
ETA: if anyone disagrees please go ahead. the last thing I want is give bad advice