JD, look closely at the block. The top is fairly thin across the channels. It then goes down over the sides of the block at the outside edges (like a cap on a bottle)
Looks like it does this:
_______
|******|
|******|
********
where the * is copper and the | and _ are the top.
pH - I agree with almost all of what you said
As far as the "trade secret" part of it, in a case like this, all somebody would have to do is get a block and they could obtain all the info you listed. For that matter, with a couple of pics it can be obtained by relative comparison with an object of known size in the pic.
In looking at the pics shown, it looks like the inside channel has a final turn to merge back with the outside two at the outlet. (hard to tell for sure from the angle of the pic)