Yes, but wouldn't it be nice not to need to?
If EW used IE's rendering engine, what you saw in wysiwyg design mode would be what you saw in IE (for static pages).
They could at least make EW fully compliant, so CSS behaves as it should. Then you would know it will look reasonable in FF and Opera, and just needs previewing and hacking for IE!
True, that's a more difficult one!