flush() with gzip

I had read a couple of references (on Yahoo Developer, maybe?) to use flush() after the <body> tag to help speed up the delivery of a page. I'm not really having a speed issue at the moment, but figured that a gain of 500ms might help save a little server stress.

The thing I'm not clear on, though, is whether this works with Gzip compression, or is using Gzip taking precedent over flush() and making flush() irrelevant?
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