Mills, you might want to try knotting it behind your back. i.e. drape the triangle over your shoulder, but instead of knotting the two corners in front, pull them under your arms and behind your back, then knot them.
This way the mousseline stays in place more, and gets in the way less in front.
Mills, I agree with Rose and Tods on this. When I wear a GM mousse to evening events, I find tying it this way not only allows the design to show beautifully and keeps it in place, but also my shoulders stay warm, and yet hands are free to eat, shake hands, carry clutch, whatever--and I don't find myself constantly "fidgeting" with it as I do when it's tied in front. One warning when wearing these as shawls--please watch bamboo and similar chairs as they can snag them.
tods, I think this is one design that is way too hard to choose between the turquoise and black. I say: go for both--if my boutique had had both in stock, I'm sure I would have too! And I still might . . .