I went back and watched all the goals the Bruins have allowed at home (not including the WC). All 76 of them. Well, 69 since 6 were ENG's and I couldn't find a replay of a Mike Hoffman goal. Here's what I've found.
The goals are all coming from high danger areas. Of the 69 goals I watched, only 6 came from a shot from what I would call the perimeter (outside and above the circles). Of those 6, 3 were blue line floaters went in, but 2 were deflected en route. The only 3 long range shots to beat Rask/Gus at home were a Jyrki Jokipakka floater from the left point that had eyes and then a Francois Beauchemin bomb off draw from the straightaway and Reilly Smith's goal from the along the RW boards. All the other goals were circles on in. By my unscientific count, 39 of 69 goals I watched came from around the top of the crease or breakaway's. The rest were mostly one timers and shots from the circles (like Seguin's hat trick).
I guess in short, the problems are mostly defense. I was expecting more "damn, Rask/Gus should've had that" goals against but they really aren't there. Maybe 1 or 2 each. The rest are just defensive calamities and errors.Things like Irwin farting the puck away leading to Wheeler scoring on an unstoppable one timer from 2 feet out. Chara blowing a tire in the corner leading to RNH getting the puck all alone in the high slot with enough time and space to shoot, collect rebound and shoot again.