Originally Posted by
Mr. Fly
Bear in mind that I'm a "plainclothes" commuter so all these are outerwear layered over my normal office uniform so my need for ventilation is likely higher than most; I also live in the SF bay area, where it only rains in winter when the temperature is a reasonable 40-50°F.
I don't think there's anything that can meet this need -- the problem is that office clothes are by themselves too heavy so you'll roast.
As you mention, capes have limitations. But for short commutes and the right circumstances, I can see them working.