The fourth level on the third row in medium had a retarded flaw, why would he put the laser that repeatedly goes up and down (it's in the middle, toward the bottom) if it can't touch you?
On F2, they think we're so dumb we would use the bottom two bouncing pads when instead we could make a platform for the orbs to go into the pipe directly.. -_- lol
For when there's multiple pipes, you know you can just solve one pipe, delete the lines you don't need to solve the other, then use your extras, unless, the pipe(s) are leaky.
There should be an achievement called " Aperture Science Snail," the goal is to make an infinite loop with two portal tubes (level 15, try to find out how!)
 "Wonderpills"){kind=icon}
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 "The Visit"){kind=icon}
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