Analysis of memory dumps isn't what I'm looking for. I don't have experience/knowledge of the internal mechanisms of Windows. Correct me if I'm wrong, but I don't think I would need to know the "internal mechanisms" of Windows in the areas like how the kernel ring 0 is implemented, or how interrupts bubble up through various levels to the actual device drivers, or how DMA is implemented with different MMUs, or how to do serial kernel debugging.
What I'm looking to learn is only the mechanisms involved with WU, DISM and CBS. So, like all the information necessary to understand enough to actually be able to write my own C# utility that duplicates dism functions like scanhealth, and checkhealth. If I could learn that level of detail, perhaps I could write a more targeted tool for specific problems rather than a one size fits all approach that dism uses (and obviously sometimes fails at).