Damn it. Damn it. Damn it.
I was trying to respond to Lee and somehow managed to delete most of his post. This is all I could save.
Lee... I am SO sorry.
And this comes back to the line I quoted above: "And, unless you already know who you're writing for, I suspect that's probably the best (or at least safest) approach."
I would think that SHOWING that you're the best writer you can be, and writing in such a way that the reader/editor/publisher will be able to IMMEDIATELY be able to visualize the comic is the best (or at least safest) approach.
I think scripts with leaden details and descriptions are boring reads, so you should only write this way when you DO know you don't have to prove yourself as a writer.