Sing "Yesterday" For Me benefits greatly from not having a traditional anime opening. The spared runtime alongside the perfectly-executed pacing early on allow each episode (at least the first 4-6) to feel unusually, satisfyingly long.
Unfortunately, the second half of the show becomes a little sloppy. Evidently, this is around the time when a lot of content from the source material was cut or extremely condensed. In a 12-episode stint, it is of course difficult to work everything in, but even though I've not read the source material myself, there's an unshakable sensation that the WRONG things were cut/condensed.
The impacts of this are primarily felt in the shows conclusion, but even in episodes prior, the story sometimes seems to wander aimlessly, almost stagnating. No one episode is a complete time waster, but certain sections are stretched too thin, and by the time significant development can occur again, you've found yourself with just 20 minutes left of the final episode.
It is an otherwise enjoyable watch to be clear, but it, at times, seemed to get away from itself after the halfway mark, leaving too small a window to wrap everything up properly.
