And sure enough, the donation went without a hitch. The entire blood-collection portion took just a hair over five minutes and I was in the lounge, drinking juice and talking politics with a couple of old ladies (it beat the hell out of them talking surgeries).
And I did get the chance to tell the nurse that my blood type is just like my philosophy in life. Be positive. She asked if that was true and I told her no, but "piss off" isn't a phenotype.