I have a Carradice poncho too, love it, but I think we're just in a different market segment; it's perhaps 'all' to an every-last-gram-shaving more 'cyclesport' audience.
(I also have a couple of pairs of brandless rubber galoshes that would be unaffected. They're waterproof but I actually wear/wore (when I was cycle-commuting) them year-round - more to protect leather soles from the pedals than uppers from the rain.)