You are trying to convince me that OOP is not related to inheritance, polymorphism and encapsulation. Sure, you can do without it. But I don't care what Alan said about it, it's still a pretty damn important part of programming with classes and objects.
And Flash is not JIT. You get some flash code, compiles it using Flash or Flex into a .swf file and then you send that file to the server. With Javascript, you get some code and just send it to the server. See the difference?
I, again, don't care what the engine will use at the end. That's semantics, we would be arguing all the way down to the hardware. The important part is: to get your AS code running, you must put it through a compiler. This is important because it reveals syntax errors, for example, includes the currently present classes around it in the file and correct general simple programming mistakes ("this class doesn't have a foo property", "this variable is the wrong type", etc).