this could
Only have been devised by McMillen.
It is actually really good, the controls are mostly accurate and the puzzles suitably infuriating for a game like this. You put plenty of thought into little gimmicks and side-jokes, I appreciate that in a game developer. The art, as usual, is extremely clean.
I think that the liquid programming however, really could have been a little more conservative. My computer can breeze through Source engine's best efforts to turn my screen into a hurricane simulation, but it can't process 300 squared pixels of green featureless puke. It could also be a little less viscous; your puke shoots out of you at high-velocity as required for some jumping puzzles but when trying to aim with some accuracy, you just end up making a giant pile of the green stuff on the other side of the screen that bonds to itself with atomic force, thus you can't go over there and get it unless you have sufficient puke to breach whatever's between it (you won't).
If I can teach myself how to utilise the power of vomit better, I would enjoy this game much more. However, when my computer is put under the equivalent strain of that of my delicate chest cavity under a dump truck, I just can't appreciate this fully.