I would put more emphasis on the grammar (operator+motion, use of case for mirroring, etc.) than on the vocabulary… and also avoid both repetition and fixed idi

I would put more emphasis on the grammar (operator+motion, use of case for mirroring, etc.) than on the vocabulary… and also avoid both repetition and fixed idioms at all cost. As for "muscle memory", it is only involved in di" at a very low level: pressing the right key on the keyboard. Deciding to do di" is _not_ "muscle memory".