A sneaky suspicion, but until last week I really didn't think that was common practice.
I think we all had our smoking gun when "Brave" won Best Animated last year.
If you could have blind-bluff voted for Pixar in any year, that wasn't the safe year to do it.
(Unless you were one of the folks pushing for Hugo to beat The Artist--
I wouldn't MIND if it'd been a fair fight, but all we kept hearing was "The Artist is the only movie this year to pay tribute to the art of silent movies! And why would famous directors do kiddy CGI movies, Scorsese should stick to his gangsters!")
That "hero" montage was really dumb and a waste also IMO. I don't think they showed one shot of any previous Batman and not a single shot of Christopher Reeve as Superman. I mean come on, Christopher Reeve IS the cinematic Superman, how could they not include one shot. Man of Steel had about 50 shots though, guess we know which studio paid the bill for that clip.
Personally, if they are going to fill the show with these clips and montages, just bring back the honoree awards.
Once in a while, when they start giving the show a unified "theme" that reflects one of the better-known lead-favorite Picture nominees, it's usually because the insiders are nudging each other that "Hey, c'mon, YOU know who you voted for...", and that the Picture that's "destined" to win will wrap up and cap off the evening's motif. And when the theme was "Heroes struggling in the face of adversity", I don't think they were expecting it to be Sandra Bullock struggling with the space capsule.
Sort of like in 1939, when there was no suspense about whether Oz or Jezebel would beat Gone With the Wind, and Bob Hope joked, "I'd like to welcome you to this benefit for David Selznick"...
(And Jon Stewart, on his second gig, tried, and failed, to make fun of the "silly, pointless" montages, with his "Salute to famous binoculars" in movies, with memorable clips from Patton, Rear Window and Mister Roberts. There was an audible silence afterwards, as you could clearly hear the audience thinking "Wait, show some more of that! ")