I have had measurements derived from 6 hour clears tossed by the NWS in larger events, so he is incorrect, whether or not he chooses to acknowledge it or not. Others have also cited instances in which it was apparent that Central Park significantly under reported snowfall in mixed events.
Its like we can sit here and see that the sky is blue, but I'm sure Chris or anyone else can scour the internet for a peer reviewed arcitcle that argues that isn't blue...not going to change my mind, sorry.