In other words, I don't think that you temporarily regress to "junior" just because you're working on something new. You still have a profound fundamental understanding of how technology works and what to expect in different situations.

This reminds me of the classic "what happens when you type google.com into a web browser" question, with its nearly infinite layers of abstraction from keyboard switches to rendering a document with calls to a display driver and photons hitting your visual receptors.

We might just be quibbling over terminology, however.