The thing about circuits is they are all an approximation of Maxwell's equations. Maxwell's equations like all wave equations have analytic solutions (in the m

The thing about circuits is they are all an approximation of Maxwell's equations. Maxwell's equations like all wave equations have analytic solutions (in the mathematical sense of the world 'analytic'), which extend to infinity in terms of their interaction and sensitivity in an absolute sense. Digital circuits are an approximation to this approximation. But the underlying reality of Maxwell's is still there. There is NOT black magic; only lack of understanding. When you do "analog circuit analysis", you MUST solve the entire circuit holistically as a system of equations which cover every physical corner. Because of this analytic solution reality to wave equations. (And yes, Schrödinger's is also a wave equation and this is the reality of origin of "interaction at a distance"). So strictly every component matters but it's to some degree of sensitivity and accuracy as specification. Taking any component out, if accuracy matters to all digits past the decimal point, will ALWAYS have an effect on the operation and performance. But engineering is about knowing how many digits past matter and how many do NOT. And there's no strict definition to go by - "it depends" mostly on the situation and requirements. I guess the author of the article isn't familiar with this underlying reality of circuits and the physics behind them. Or the author is overselling what is trivial for signaling something other than truth or the facts.