What's hard to understand about hot boxing a train?

One of my more memorable experiences on the LA Metro was walking into a train that smelled like 100% bona fide human fecal matter. As in, there is almost no way that if you went looking you would not have found a huge pile of it in some corner. Naturally, everybody went about their day acting like nothing was wrong. Except for one guy, who pulled out a huge blunt and just started huffing and puffing on it until eventually the weed was on-par with the shit, and later ended up totally overpowering it.

I personally prefer not to involve myself with weed, but there's no denying it's a better experience than huffing literal shit.

On a train, a hot box is a failure of a bearing on an axle, resulting in heat, often smoke, and sometimes fire. If it's not caught in time, it ends up with the axle failing from the heat, resulting in a train derailment. It's a "stop this train sooner than immediately" kind of problem.

It's not the kind of thing that people do to a train.

Oh, hot boxing is smoking weed in a vehicle or room with the windows closed.

I could see how the rest of my comment would sound a bit tangential without that context.

Oh wow I had no idea that was a real train term! What about clam baking a train?

So far as I know, clam baking has no, non-weed-related meaning for trains.

Clam bake. Don’t know hot box was a real train term! It’s when you smoke weed so it fills up a space, commonly a motor vehicle.

Didn’t know*