But even though it doesn't win heads-up, it could be equally effective against other strategies, particularly if they are reallly dependent on a single card that could really screw them up if skipped with oracle.
I was just thinking about this, and actually oracle-BM might beat smithy-BM or envoy-BM from first position, since you have a better chance of knocking out their key card.
EDIT: just simmed it, and while it has a first-player advantage, it's not as big as envoy-BM vs envoy-BM