Yes, I think it is, technically. It fits the spec’.
I think this brings to light the serious lack of an American Sandwich Association. We Brits have the British Sandwich Association and after Googling for 30 secs, I couldn’t find an American one so it therefore must not exist. That, to me is concrete proof that we are in fact, the sandwich masters. In the states, with proper education and guidance from us, these sandwich-burger quandaries would be ironed out once and for all.