Planning is Just a Way of Avoiding Figuring Out What To Do Next
The idea of planning and plan execution is just an intuition based decomposition. There is no reason it has to be that way. Most likely in the long term, real empirical evidence from systems we know to be built that way (from designing them like that) will determine whether its a very good idea or not. Any particular planner is simply an abstraction barrier. Below that level we get a choice of whether to slot in another planner or to place a program which does the right thing. Why stop there? Maybe we can go up the hierarchy and eliminate the planners there too. To do this we must move from a state based way of reasoning to a process based way of acting.