Your reading comprehension skill suck, and you are assuming that 3 heroes can hold vs 5 heroes in the other 2 lanes. Not all decks are black. Not all decks have access to time of triumph/quorum emisarry/ so on to rush ancient. It is always easier to kill 2 tower over rushing ancient if you aren't playing black and even if you do, he could be running black/red as well and hero-deny the shit outta you in the other 2 lanes making you unable to play cards while he can.
Dont teach me how to play the game unless you're lifecoach or swim or with demonstrably better winrate. With my kind of winrate I clearly know what to do. You offer a basic play that can be dispelled 95% of the time.