Everyone learns differently so if it helps then by all means. I just worry that it might be similar to some of those phone apps where it feels like you’re making progress because you’re checking off boxes, but you’re not really learning very much while doing so. The problem with learning grammar by memorizing one example sentence and repeating over and over again is that you will later encounter sentences that don’t follow the exact pattern you’re used to, and if your understanding of the grammar point is only in terms of a single example, then it might lead you to struggle or ask “why does this sentence not look exactly like that one example I learned?” When really, learning grammar should be more about recognizing patterns and understanding how they work in a variety of different settings and in combination with other elements. I think it’s especially important for some grammatical words in Japanese that attach differently to nouns, adjectives, verbs, etc., where if you only learn one example sentence with a noun, you might form that pattern wrong every time you use it with a verb, or fail to recognize it when you see it used with a verb and so on.