Taking the pressure off -- working on paper (updated)

I've been painting in Montana for a few days now and it's a humbling experience.  It's beautiful and the weather changes at a pace that makes me paint in a frenzy.  I've been working by the Gallatin River where a stream comes through the woods, working on canvas and trying to warm up to being outdoors painting again.

Today I decided to take some of the pressure off -- working on "multimedia artboard" instead of on stretched canvas.  It's a paper-like substance, very stiff and heavy, and purports to support oil paint.   It allowed me to work more quickly, both because it's small 8" x 10" and because I set myself up on my deck (yes, that's the hot tub cover I'm using as a table) in case a sudden rainstorm hit.  I managed to get two quick paintings done between rain showers today.