>Companies like Comcast have no interest in slowing down web site traffic

Yeah? How about money?

As a comms engineer, I too think about the technical implications of this.

But you have to remember that the people who push for the abolition of net neutrality are mainly the finances guys, i.e the ones responsible for bringing as much money as possible to the company. And when you put yourself in their shoes, all of a sudden you get dreams of Comcast turning the Internet into the same kind of market it has in cable television. And you very quickly forget about QoS, bandwidth, latency and the job of "delivering the bits" and just think in terms of profits. You wouldn't know what most of those terms mean anyway...