Kirchoff's Rule, Superposition, Thevenin's and Norton's Theorem

I was in this PALSI meeting where senior students guide the freshmens on homework and everything, trying to understand the connection between these 4 rules when people are trying to say, " Its enough that you know how to do it, just learn how to do it and get the right answer.". I was like "WTF? Are you guys even learning physics at all?"

It took me quite not a few hours to prove that they are related in some manner.

Kirchhoff's Rule is powerful enough to solve almost all circuits with batteries and resistors, how about if a current source is present?

From "Basic Electronics For Scientist" I get to know that alot of the formulas we get will stack with each other, so we must any how determine which one is useless and eliminate it. A common way to get through this is not to loop 2 loops individually that originate from the same battery

We just ignore the current source when we are calculating Total V in a specific loop, any current source that is encountered can be ignored.

200V = 47I3 + 4I1 + 23R4

And for The 2nd law of Kirchhoff where current never changes at any Nodes,
20A + I1 = I4