If you read much of this blog in the beginning you know that although I fully sustain and believe in the prophet, I do not believe in the infallibility of our prophets. That is why I feel comfortable in thinking that BY started the priesthood ban incorrectly, JMHO. Here is a very interesting article at BCC that sounds like a plausible reason for my own only concern with the issue...if it was an error on BY's part, why didn't it get corrected earlier when David O McKay and others wanted to correct it.
Enjoy! David O. McKay and the Priesthood Ban