I'm definitely giving it a try.  I have made a cordura head piece and i'm going to rig it up maybe this weekend and see how it feels.  My canoe is fairly light at 43 lb but I have to say that I'd rather carry an 85 lb pack than that canoe simply because of the weight distribution.  Getting a bit of weight off my shoulders and on to my back seems like a plan to me.  I guess I'll find out.  As for using adjustable cleats: given a choice between adjustable and non-adjustable why wouldn't I choose adjustable - there's no extra work involved.