Hmm..I think it will as long as you don't expect the fabric to look like it would with all one weight. I think a scarf is a good choice for this method really. I say go for it and after 5-6" if you don't like frog and find something else.
When asking questions ALWAYS post the name and a link for the pattern if you have it.
It could be fun to leave lengths of yarn at the beginning and end of rows in particular sections and knot them to form a fringe. And if you are looking for a more consistent width, maybe try knitting the heavier yarn in a smaller sized needle than the lighter yarn.