dvilayphet

Fair enough.
For L2 and L3, the questions get more tricky so memorising the formula isn’t good enough. You need to understand what the formula is doing so you can apply it properly to the specific set of circumstances you are given.
You’re right, it’s not always plug and chug.  However, you don’t need to know how to derive the formulas in order to understand how they work (eg, that a plus sign indicates that two things are positively related).
I interpreted this person’s situation to be that they are good with numbers (ie, capable of abstract though) but don’t know all the ‘procedures’ that one needs to know in order to, for example, solve differential equations.