While making this movie, I discovered that holding down as the current block hits the ground will sometimes change the order of blocks. It seems to have very limited application, though (since you can only choose from one extra block). I used it once or twice in this movie.

This is because holding down for at least four frames (at least two frames before the block lands, the frame it lands, and one frame after it lands) causes the next block to appear one frame earlier. Holding down for at least six frames will give you points as well; one point for every two frames beyond the necessary four. There's also a small window for manipulation just after the current block lands and before the next block appears (starting at 11 frames before it appears). This window is five frames long, which allows pressing and releasing left+right+down up to three times, each of which delay the next block by one frame (typically giving one the option between four different blocks, which is usually enough). This has a nice side-effect as well, in that it doesn't cause the current block to flash, but only the next block, which is even less distracting. I know all this because P.JBoy suggested that perhaps Acmlm existing run could be modified to use this form of manipulation instead of pausing. I decided to give it a shot, but unfortunately, it's not possible. Left+right+down interferes with moving pieces left and right, and with pieces stacked very high, the window for manipulation just isn't large enough.