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Nope, common sense over rules here.
where the heck do you think the nails for the shingles go though? so nailing down would not compromise I/W membrane.
the reason you have ice shield is so that the melted water penetrating the roof surface (top layer of shingles) does not reach the decking.
the ice would build up and when the snow/ice continues to melt, the resulting water would never reach the top edge of the I/W, because of the roofs' pitch. The ice dam that is there would also melt as the melting snow. so the water would be carried away over the top of the ice.
my guess again why its has an adhesive backing is. for the ultimate protection. the manufactures doesn't give a rats ass about the guy doing the reroof 20 to 40 years down the road.
you do not need to stick the shit down. the bond is not that good and certainly not strong enough to stop the expansion of ice. which btw is never the problem. the problem is ice on the surface not below the ice shield.