Thanks! That makes sense. I could be wrong, but I think a lot of this is because FCP 4 doesn't speak h.264 and doesn't take good advantage of the hardware. When

Thanks! That makes sense. I could be wrong, but I think a lot of this is because FCP 4 doesn't speak h.264 and doesn't take good advantage of the hardware. When/if you can switch to FCP X or a modern competitor (not saying that's an option yet, necessarily), I wouldn't be surprised to hear that most of these annoyances go away.