And the tragic thing about "this" being a magic keyword that looks up a dynamic value in the runtime, instead of a normal lexically scoped variable like it appears, is that 90% of the time "this" is exactly the thing you want a closure to close over, so you have to do ridiculous stuff like "var self = this;".

Even knowing this rule very well and being totally hard core OCO (Obsessive Compulsive ORDER, not Disorder) about the code, I still make "this" mistake ALL THE TIME, so whenever something weird happens, "this" mistakes are the first thing I look for.

"this" is such a terrible design flaw, it bites me even when I'm expecting it.

The way I think about it ('this' being like any other object), closures are just supplied a default 'this' object (window, in the case of web), and instead of providing a this argument via the argument list, you can choose it with the apply/call/bind functions.