>> Despite what we hear is a serious rash of over-dressed staffers at the Corcoran Gallery of Art running off to “dentist appointments” with updated résumés in hand after several high profile dismissals were announced earlier this month, there appear to be several good reasons to head down to the beleaguered museum. The first major retrospective of the work of Robert Bechtle, the San Francisco-based painter known for his photorealistic streetscapes, is up through June…