...You're not alone!
I myself am fucking tired of slogging through boring shit due to "story" reasons. I say the same about all games, if I had this stuff on an emulator I'd fast forward thru the slow sections. I play these games for the action!
It's why Uncharted 2, while still amazing, isn't my favorite game of the year. I can't skip the in-game cutscenes, many of the platform sections are boring, and many events in the game (see the train intro) serve no purpose other than to slow you down. I want to play a fun game, not watch a movie!
I can't say too much about Assassin's Creed 2, because to be honest, I couldn't play more than 1-2 hours of it. That intro killed it for me (I don't want to get to know the assassin, I preferred jumping right in as Altair). I watched my bro play through the game, though, and there was way too many... well, puzzle elements. I'd agree the boss battle was disappointing, it wasn't much of a fight. I blame the focus on story... I've been playing Gears 2, and it has the same problem.
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