This is fantastically put. I’ve actually been considering the idea from the opposite direction — that is, you do the ‘mom test’ and not care about any high level trends, because mainstream opinion on what’s a ‘current’ trend probably means that you’re too late to the trend — or at least its effects are too diffuse — for you to take advantage of. What seems to have worked instead is some form of
You discover something that works.
You have no idea why it works but you keep exploiting it.
You eventually realise that it works because of trend X, which you stumble upon in some mainstream publication a few months after you’ve already started exploiting it.
Thereafter, when you tell the story of what you’ve done, you make it sound as if the trend was obvious to you from the beginning, and that your activities are genius-level exploitation of said trend.
(I’m aware that Gurley’s path might be similar to this, as well!)
Dammit, your description is compelling. I’ll need to find myself a copy.