The JFH, aka the Jimmy Flloyd Hasselbaink, aka the tight smile was invented by Jimmy Flloyd Hasselbaink in early 2004.
The tight-smile is the product of a beaten man (or woman) trying to put a brave face on something but giving away the gravity of the situation through the insincerity of their smile.
They don't fool anyone.
Feel free to contribute your own by emailing them to hjr456y AT gmail DOT com.