At most, practice makes permanent. Only perfect practice can make “perfect,” and that ain’t gonna happen this side of the Jordan. . .
Still, practicing a musical piece. . . so many different methods, and choices/successes depend largely on skill level and preferences, but I always preferred reading through a piece and listening to it “between my ears” as much as possible before setting hand (and mouth, depending on instrument) or voice to the music. *shrugs* During a quick read-through, I could generally identify places that might need special attention, and could often iron them out, at least a bit during the scan. Then it was mostly discerning and effecting the teleos of the piece, as I inferred it from the leading of the tune and harmonies, as well as the composer’s directions on the page (notes and signs and etc.). When leading a group through a sight–reading. I came to appreciate the STARS method for young/inexperienced/amateur performers. For a group with more developed music literacy, just walking through a piece and noting to the group where I thought the different sections (or the group or the piece or both) might require a bit of attention. That was usually enough to get that attention paid during the first sigh reading session. Usually. *heh*
With volunteer choral groups, I preferred handing out an abbreviated rehearsal schedule, with bullet points derived from my much more detailed outline for each piece in the schedule for that rehearsal. Kept things moving and saved time. Of course, I had to remain flexible and touch on unanticipated issues though those were usually rare. A fav book on choral conducting informed the time I spent doing that. . . I occasionally had voices like those referred to below, and I celebrated their inclusion:
“I have never paid much attention to the ‘quality’ of a choral candidate’s voice. I am much more influenced by the extent of his desire to sing, and by his interest in music. . . May I offer an extreme example of this indifference to vocal endowment. I once had, as members of a chorus, two monotones. It would be impossible to exaggerate the delight they experienced in having a part in the rehearsal of great music, and had I denied them one of the real resources of life, I should always have regretted it. They were not the least sensitive over their deficiency and made no protest at being seated together a little apart from the chorus. Fortunately, their voices were not strong ones. They sang, without deleterious effect, not less than four major choral works with the Boston Symphony Orchestra and its conductor.” —
_Choral Conducting_, Archibald T. Davison ©1940, sixth edition: 1950,pp. 27-28.