Why were these things removed from the game? [closed]

Does anybody have a source as to why these awesome things didn't make it into the game?

The pneumatic diversity vent: http://www.thinkwithportals.com/media_05.php

This level: http://www.thinkwithportals.com/media_07.php

Is it possible the game could be updated with this content in the future?

EDIT: It's as if I knew about it, except I didn't

The puzzle from the repulsion gel intro appears like a fairly direct port of part of a Tag: The Power of Paint level, and that as an entire chamber is fairly basic and doesn't teach much except timing. Stylistically, crushers are fairly absent from the single player campaign, so it doesn't fit well.

According to The Final Hours of Portal 2, the pneumatic diversity vents were removed "at the last minute" after some high-level executive review, as they weren't found to be working well in test chambers. Ultimately, the mechanism of using portals to knock stuff around can also be accomplished with the blue paint, so they may have wanted to avoid duplicating functionality.

Likely they were removed because Valve thought they made the game too difficult.

The test chamber in particular required exact timing.