This is not a CQRS article, rather, just a technique to thin down a controller code — I’d say it’s more of the mediator pattern.

Also, regardless of the component naming (ICommandHandlerFactory, ICommandProcessor, or ICommandDispatcher), I believe the whole point of this is to resolve the handlers (those of command or query) and to make the client (the controller in this case) needless of knowing the internal process of that.

And not sure if I’ve got your point on IoC and the Installer level.

Cheers,