Carolyn, thank you for your very quick answer! I knew you checked in now and then, but wasn't sure how regularly you visit a particular thread, since there are so many other threads (and forums) needing your attention as well.
I appreciate your very helpful clarification. That's what I suspected, since you did specifically call out BER for some varieties. I'm having better luck this year with the varieties I picked using the book for guidance, especially Boxcar Willie. Though I've still been able to inflict BER on a couple of varieties that you hadn't seen it on.
I'm really enjoying the learning experience, though!