You can't add much more indirection than making someone credentialize in a manual to do something as trivial as showing timestamps. Better hope you catch that one-liner tip and then remember it when you're back in the app at some other point in time.

I'd rather every app just have a hamburger menu with a menagerie of settings so that those settings can exist even if they're too hard to design for. Instead designers write blog posts that shame everyone for making those menus in the first place.

Hidden gestures is the worst UX of all. For the same reason Siri will never replace a CLI -- completely probabilistic, unknown interface.