It doesn’t become less effective for me, as much as I don’t need it anymore as my language ability progresses, then rely on it again if my ability regresses. I’m a nonnative German teacher in Germany and while I don’t have to jog my memory for standard conjugations, if I learn a new verb that has a short i in present tense and a long a in preterite, I’ll still chant “singe, sang, gesungen” in my head. It’s just different learning styles.