Hi Colin. Thank you for your nice words....however, I do not completely agree with you.Thanks to LvW for his patience and persistence. Our minds obviously work differently and it took a few exchanges for each to understand the other.
I do not think that our "minds work differently".....I am with you regarding the aim to conceptually understand the working principles of parts and circuits. I really think that this is always the necessary background for designing circuits - that means: Not blindly follow any formulas or design rules but to know what happens within the circuit - and why !
(Remark: For example, that is the reason I must know how a transistor really works - voltage or current controlled - although in many cases, this is not really relevant for designing amplifying stages..)