Not at all! Dreamweaver is simply a rapid design tool. Its Design View/Code View split mode is ideal for seeing how code influences your design. Even more so if you are doing WordPress theme development (see ThemeDreamer.com extension for Dreamweaver).
I love the way you can just click in Design View and instantly see 'what code does what'. Dreamweaver's Design View mode is an interesting animal with its own rendering nuances, but it sure does beat the heck out of what I call 'trial and error design' (the tedious editing/saving/uploading/browsing/refreshing cycle). Design View can give a good 'approximation' for instant changes in realtime. Is your time valuable to you? Its certainly NOT a cheat to use Dreamweaver (esspecially now that it works with WordPress)!
:-)
When it comes to design, Dreamweaver's Design View is handy. Its just an 'approximation' view, but unlike hitting refresh, or configuring servers local and afar, Design View is instant, realtime, and requires virtual no configuration.
If you're a Dreamweaver user you may want to check out ThemeDreamer. The newest version links right into the WordPress online documentation as well as provides code hints in Dw's Code View window (I prefer the split screen mode with Design View myself). You need this Dreamweaver extension to view WYSIWYG of WordPress themes in Dw's Design View. In fact, I think its the only way to get a WYISWYG editor for WordPress theme design.
You can see before after shots here:
http://www.themedreamer.com/demos
Hope it helps if you have any Dw or WP questions, just let me know!
If you are using Dreamweaver and WordPress you may want to consider getting a Dreamweaver extension called ThemeDreamer. It provides WYSIWYG in Dw for WordPress theme files.
You can see before/after screen shots here, as you can see w/out it Dw is pretty much dead/notepad...
http://www.themedreamer.com/demos