my Buick has the hinges you speak of. once, my hood actually did come open on the highway. I had been installing my cd player and had disconnected the battery, and when i re-connected it, for some reason i just gently put the hood down and didnt latch it. when i got to about 45-50 MPH, i heard a CLUNK and the whole hood popped up about a foot in the air relative to where it was originally, but thats all it did (the front of the hood pops up a little first, then you tilt it forward). i had to go home and change the undies.
