I found the following comments on direct and indirect control in "Survey on iterative learning control, repetitive control and run-to-run control." by Wang, Gao, and Doyle:
There are two application modes to use the learning-type control. First, the learning-type control method is used to determine the control signal directly, and this kind of learning-type control is called direct learning-type control. Second, there is a local feedback controller in each cycle and the learning-type control is used to update the parameter settings of the local controller, so this kind is called indirect learning-type control. The methods that can be used for designing direct learning-type control and indirect learning-type control will be discussed in Section 4 and in Section 5, respectively.
What is the difference between direct and indirect learning control? My understanding is that in indirect control you can alter the control parameters and the input signal as opposed to just the input signal in direct control; is this correct? I also do not understand the significance of a "local" controller.