Anyway, he's something entirely non-linguistic.
I actually learned this a few months ago (or maybe late last year), but I forgot, and have just been reminded of it again.
So, you're on a building site, let's say. A guy wants to lift a heavy pallet by attaching them to a cord with a hook on the end. The cord can be steel, jute, kevlar, whatever, doesn't matter. I believe it can also be a twisted rope or cable, though it might get a bit trickier in that case; I'm not sure if it applies to more complicated plaited cords, linked chains, etc - I suspect it basically does but there's more complicated factors in practice.
So, they lift the pallet, but you want to save trips so you load more and more items onto it. But oh no, you overload it! The steel wire (for example) holding up the pallet snaps. Oh dear. But it's OK, the guy has another steel wire. It's the same type of wire - in this case, the same type of steel (I believe if it's a twisted rope it needs to have the same number of strands, degree of twist, etc, for this trick to work), but it's not the same thickness.
Now, you've already found out how much weight the first wire could lift without snapping. But this wire is a different thickness, so how do you calculate how much weight the new wire can lift before IT snaps? It's OK, you can measure the thickness of both wires to compare. But what's the equation you have to use?
And what I've learnt/remembered is: it doesn't matter!
You can solve the problem through a practical method, without any equations. All you have to do is, if necessary, go back in time (or have been lucky/clever all along), and, as you put more weight on the pallet, keep flicking the wire with something to make it go 'twang' slightly. Observe how high-pitched the 'twang' is just before the wire snaps.
Now, in the current time, with the new wire, keep flicking it as you add weight, and stop when the 'twang' has risen in pitch to just before the pitch it made just before it snapped last time.
Why does this work? Because of a beautiful law of nature: for a given material and shape, a string will always snap at the same pitch, regardless of its thickness. The thicker the material, the higher the tension it can withstand (in this thought experiment, the more weight it can bear). The higher the tension, the higher the pitch of the twang it makes when you flick it. so the thicker the material, the more you can raise the pitch of the twang, by increasing the tension. But the thicker the string is, the lower the pitch of the twang it makes at a given tension. And miraculously these two factors exactly cancel out, so that the string always breaks at the same pitch, no matter how thick it is!
This has almost no real-world utility, but it is strangely cool.