Just trying to equate it to a behaviour I've observed before in my physics work: Is the block a real level block or a model ?

The fact is, some intern built a model here with several inverted faces (their normals facing the wrong way) and when a physics entity hit it it was accelerated instead of bouncing off of it. The intern had the nerve of suggesting we use it as a "nitro" feature in a racing game... I almost beheaded him... But I digress.