Yup just as weird as Dalton having lots of good stretches but according to Dolphin fans both him and Marvin Lewis are terrible, and always have been.
Andy Dalton's a terrible example if we're talking about coaching and supporting cast. He's had the benefit of working with great backfields, a good offensive line, very talented receivers (including AJ Green, a top 3 guy), and on top of that he benefited from being coached by Jay Gruden (one of the best in the business) and Hue Jackson (historically a very good OC) before they brought in the much less accomplished Ken Zampese and Bill Lazor.
For most of his career, Dalton's been in a situation that would make almost any other NFL quarterback envious, and the results have consistently been underwhelming. There's a very simple explanation for it, too. Andy Dalton's got a rag arm and can't challenge defenses in tight windows or on the perimeter. In my opinion, his ceiling is low tier starter / great backup, and it's entirely because of physical limitations.
I don't dislike the guy one bit, as he seems like a good person off the field and Miami's had success against him for the most part. He's just not very good.