I then learned about Thevenin / Norton and began working some problems and then I realized that Thevenin / Norton isn't much more than the previous general transformation problems I was doing previously (am I right?). For example, when I did general transformations as described in the first part and ended up with only a voltage source in series with a resistor, then this is exactly the Thevenin circuit... (same with Norton and the current source parallel to resistor case)... Am I right?

It seems to me that Thevenin/Norton is the very same general transformation and simplification I was already doing in the first place... Am I right?

Say for example I begin with a large circuit and simplify it down to a single voltage source in series with a resistor at the left of terminals a and b.... This would be exactly the Thevenin circuit... All Thevenin/Norton do is giving "alternative" methods to find the same equivalent circuit (which I am not even sure it is easier... in this case, what really is the use of Thevenin/Norton?)

I just want to make sure Im understanding correctly

Thank you