Toe Up or Toe Down with a Driver?

Mark Crossfield delves into the question from Andy Blackwood,  "with the Driver should it be toe up or toe down through impact".

Mark gets this question a lot when people see his numbers from his GC2 launch monitor. A lot of people think the Driver should be going through impact flat to the ground, but with the nature of the flatter swing it is only natural for this to occur.