HL scripted sequences (there were a LOT in HL1) are not like other games. (They're much, much better.) Instead of showing you a little move that you sit passively by and watch, the scripted sequences are things that happen AROUND you WHILE you play the game. That way, you aren't taken out of the game and back into "observer in the real world" mode. I don't know why other games have been sooooo slow to pick up on this.
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