There seems to be a horrible confusion in some people's minds between "no effect due to icing" and "no icing on the surface".
I don't believe anyone at an OEM in any way inviolved in the design for flight into icing would ever say "flying surface X doesn't catch ice". If they did, they need to find a new job, because every flying surface on every aircraft ever made collects ice. It's the basic physics.
But I do believe that they could easily say "there is no (perceptible/significant) effect of icing on surface X". By which they mean "a pilot can't (easily) tell if there's ice on that surface" so we can, in most cases, just ignore it. I know I can happily make exactly that statement for many of our aircraft, with respect to ice on the tail; unless you're really paying attention to the trim required, you'll never spot the effect of ice on the tail. Because by design the tail is nowhere near stalling anyway, so a slight shift in the efficiency of the tail is all you see, which just shows up as a shift in the stab trim you use.
And yes, if you really work at it, you can even defeat that assertion - go fly in SLD, for example, and all the OEM's work for icing certification is valueless, and your only defence is to get the Hell out of the SLD, because we have virtually no idea what will happen - but we're pretty sure it'll be nasty.