John, you can do that if you so desire, I just brush it on the entire area to be painted and that's it, one coat of future, even from a brush is very light, doesn't go on heavy at all. I use this method a lot, specially when I do the masking for the windows of today's modern cars which, as you know, are mostly black.
Tamiya tape works great even if you skip this process, I just like to be safe and also, I am a little picky....