This is really cool, but I think you add that extra white outline when you often don't have to. Your stuff is usually so well planned that you're (that I am) able to read black-on-black and understand the shapes even without the extra white outline. Just a thought.
THat's a good critique and something I ponder often.
The reason I use it so much is that my brush strokes are pretty fat, and if I spot black right up on the subject, where the object begins isn't really where I wanted it to begin. It's somewhere in the center of that stroke. Does that makes any sense haha? Also, when colored the outline should be a dark grey to almost get rid of it.
I dunno man, good to know. I'm always up in there air with it myself.