Through the first three weeks of the season, the Dodgers had the most dangerous offense in baseball. Over three frustrating weeks since, they’ve been perhaps the most mediocre unit in the majors. Reconciling the difference has become the most pressing storyline surrounding the team to this point of the campaign –– raising questions about what has gone wrong lately, how fixable the lineup’s problems are, and whether the Dodgers’ true talent level is closer to what they did out of the gate or what they have endured more recently. “Just kind of as a unit, I don’t think that we’re one piece right now,” manager Dave Roberts said Sunday, after a 7-2 loss to the Atlanta Braves that dropped the Dodgers to 9-12 since their offensive slump began.  A four-time MVP, Dodgers star Shohei Ohtani is struggling massively at this plate this season. IMAGN IMAGES via Reuters Connect “It’s not from lack of effort,” he added.…