Is your reasoning that of an experienced, competent cryptographer? Because mine isn't. I'm not a cryptographer's peer, either, and I'll bet you aren't either. Step one--nobody said step all, but step one--is establishing your bona fides to determine whether it is worth burning cycles on your idea, because proving or disproving cryptography is very hard and very time-consuming. It is a heuristic that, generally speaking, works pretty well.
No, his reasoning probably isn't. But without putting words in his mouth, there is this quasi-religious "thou shalt not talk about cryptography" attitude among programmers like crypto is literally voodoo magic. The appeal to experience is an incredibly frustrating part of this. It's like people are willfully ignorant and forcing those of us who may not be experts but also want to have an intelligent discussion to pretend to be idiots along with them.
I would agree, except "standard security measures" aren't and you lead to travishamockeries like the pepper nonsense. Which is why I default to, "cite your sources."