On the radio pregame Cory asked Molitor about the sliding thing. Molitor's response was basically: if you practice sliding you over think and it wont be as natural, and they hoped his baseball instincts would take over in a game and a slide would be fine.
not excusing it or agreeing with the reasoning, just saying what the manager said.
I suspect they may have just told Sano privately: "don't slide"
That may not play well publicly, though.