[Joker_vD]

> Why the hell receiver of a message gets to dispatch the implementation at very late moment? Why not context?

Well, then it is the context who is the actual receiver, isn't it? Since in this scenario the object may never even receive the message since the context has already processed it on its own, so calling it a "receiver" would be incorrect.

> a composite object of an int and a float receive message „add“ - who decides which implementation to use

The composite object itself, who else? It can do anything, including doing nothing, or not using any of their implementations, or dividing its int by its float, etc.