Quote from jimrockford:
IB solved this particular problem by giving us the option to exclude NYSE from SMART, and it works very well for a lot of people.
I think an even better step forward would be to give an option that lets SMART route to NYSE, but ONLY when immediate automatic execution is guaranteed through the NYSE DIRECT+ facility. IB theoretically has this option, but it never actually worked, because of bugs in the logic. They plan to fix it someday, but they are treating it as a low priority item because few seem to care about it.