"""For example, any website I've built I can surely make with just a text editor but I'll lay it out with ps first. That way I can go back and check what colors / gradients / dimensions I used to speed up the process."""

You may be a bit behind the times:

http://37signals.com/svn/posts/1061-why-we-skip-photoshop

http://24ways.org/2009/make-your-mockup-in-markup