My understanding is that TDT and UDT are supposed to be used by an agent that we design. In all likelihood, we will have decomposed the agent into program and data in the process of designing it.

Reading this statement, it comes across as quite objectionable. I think that this is because dividing something into program and data seems it cannot be done in a non-arbitrary manner--many programming languages don't distinguish between code and data, and a universal Turing machine must interpret its input as program at some point.