I think the overriding point here is that you were asking Mo to divulge proprietary information that went into the design and production of his machine, which he does sell for profit. Maybe you weren't going to use whatever info he gave you to build a derivative product, but others might have and if Mo puts that information out on a public forum, he's shooting himself in the foot.
Without talking to Paul, I think he was trying to gently stop the conversation before it got to the point where Mo himself was going to be forced to come across as rude to you. You kept pushing and Paul finally shut the conversation down. The way in which he did it, by the way, didn't come anywhere close to d**k level, IMO.
Besides, if I'd put the kind of time into building a reliable, accurate tool like the Determinator, what is there to gain by telling someone how to build their own? If I'm trying to sell $1,300 Determinators, I want people buying my $1,300 Determinators. I don't want there to be a bunch of homegrown products out there competing with my design.
And if it's as difficult to do as Paul says it is, he may have been trying to save you a headache. If you build one, you're going to have to find someone who does have a Determinator in order to test and verify yours, which you'll have to do by testing literally dozens of balls in order to get a reliable sample. Otherwise, you'll never know whether yours works or not.
Jess
