you should feel these circuit, an analog designer needs many intuitive knowledge, also need to know many rule of thumbs.
For example: R parallel with R equals with R/2, the step respone is exponential type for the RC (for the other RC 1-exp), from the slope and the final value you can see the tau etc.
very important to feel these STC circuits, after the LC, RLC circuits, after the intuition to make from pole-zero chart a Bode plot,a time domain signal...
and from a complicated analog circuit (20-30 transistors) sketch the pole-zero map.
Believe me these things are very important.