I agree, that in this case the method that you listed would make it easier to access your site before DNS propagation, but as I said, this is more to do with the way DreamHost does things behind the scenes.
Overall, I like the way DreamHost has things organised. It can be a pain to setup sometimes, but it does provide a lot of versatility in many areas.
The method netdcon outlined (modifying your hosts file) seems simple enough and would only take a few minutes.
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