White Bear theatre, LondonMark Carey's play asks why the former best-loved man on TV has been so thoroughly expunged from our comedy pantheon " but doesn't have a great deal to add TV has mined a rich seam of golden-age comedian biopics " but Benny Hill has yet to be afforded the posthumous privilege. That's partly the point of this stab in that direction by Mark Carey, which asks why Hill has been so thoroughly expu…