Stop with the "bad design" nonsense. Stop glorifying flat learning curve. A car is not intuitive to use, you would never guess what it is for if you didn't see someone using it. Neither is a pen (you spend years mastering it). How about special moves in fighting games, not to mention combos or fatalities ? How would you learn that without being told ?
The only thing Black Mesa did wrong is not including the Hazard Course. I encountered the mechanic earlier, where it was intuitive (little room between a box and the ceiling) and it was obvious I had to both jump and bow down to fit in. I'm a curious player accustomed to sniffing for secrets. I try combinations of keys just to see what happens.
I find myself more and more drawn towards board games. In the realm of board games, having to explain rules is the norm. Retarded people are left out unless they have a will to learn (and I met one of them who has more forward-looking attitude toawrds learning than many modern gamers). To play board games, you have to make an attempt understand them. Meanwhile in casual games, there's this awful notion that anything that's not immediately obvious is evil.