Richie,
I'm glad you enjoyed it. You'll have to send some pictures of your SV. I'm interested to see the results!
I had a few very similar to your BM. The graft takes, but for some reason the tree doesn't have enough sap to force growth through the grafted bud. My theory is that the rootstock eventually dies because no sap is flowing to any new growth, so the tree naturally gives up on it and tries to put out new growth from the base or a lower bud. I figured taking off those lower buds would probably be the best bet because then the tree would focus its energy on the graft, but that's not the case because the tree eventually gives up on the entire trunk and you've got nothing left.