I think it was Ken Levine, over at his blog, who said - if a film is over three hours long, it should not be eligible for 'best editing' in the Oscars.
I would agree.
Long films are often a chore. Not always. But often.
For example, I was bought those extended editions of the Lord Of The Rings films each Christmas three years running.
I still haven't watched them. It's not that I don't think I'll enjoy them. It's just that amount of time is a serious commitment and I can always think of several other shorter things I'd rather do. And I have to wonder, will they really be better movies than those already long movies I saw in the cinema? If anything, that Ent sequence needed to be a lot shorter.
More often than not, I find that cut scenes are cut with good reason. For example, the extended cut of Aliens added some good scenes on their own, but broke the flow of the movie in several places. Most importantly, they took the movie from being Ripley's story to something far less coherent. The DVD of Donnie Darko had the deleted scenes with commentary from the director in which he explained very well why those scenes didn't belong in his movie. The "Director's Cut" recut those scenes into the movie and, as it happens, it turns out he was right the first time.
I enjoyed Watchmen earlier this year.
And I'm looking forward to it on Blu-Ray. But it seems the Blu-Ray version is 3 hours and 10 minute. Now, at the theatrical two and a half hours, that film was on the edge. It kept me interested but was definitely on the edge. And, as a fan of the source material, there isn't one thing cut from the graphic novel that I missed in the movie. Do I need another half hour or forty minutes added to it?
No. I do not.
More does not equal better.