Photoshop and Dreamweaver here.
I do all my coding by hand and hardly ever use the preview in Dreamweaver. Where Dreamweaver excels is in things like link updating site wide.
For example, I am working on a 100 page hard coded site at the moment. If I move a file from one directory to another the links update site wide. If I change a file name, likewise. It also has site wide W3 validation & error checking which is useful for double float margin bugs, guilotine bugs, 3 pixel text jogs, expanding box problems, etc. etc.
I'm sure that other editors do all this as well, this is just what I am used to as I've been using it for years.
You really should know HTML and CSS though. You should be able to open notepad and just get down to business if need be.