This is a discussion forum. Bob’s expertise is beyond reproach. IMO he was not trashing it , more saying there are better options. Your sensitivity seems to suggest you have some attachment to this training aid. Rather than call Bob out, how about you elaborate on why you think Bob is wrong. Again this is a discussion forum.
Did you not read what he said? He flat out trashed it. How do you not understand that? He has not even tried using this aiming aid.
If you're selling a used car online, and I comment and say, "Man, that car sucks, there's better, cheaper cars elsewhere". That's pretty rude of me to say that, right? Especially when I've never even tried your car out. But hey, this is a discussion forum and I can talk shit about your car, right?
We're all here because we like pool, right? I didn't know that it was a
requirement to speak up and ignorantly talk trash about something a person is trying to sell.