I did a quick google search to see when the internet claimed Nashville jumped the shark. It seems the consensus was season two. I'd have to say it was when Connie Britton left. Her facial expression could save any dire plot turn. Now that's Acting. For the die harder soap fan, we have no choice but to keep on watching.
They should have ended it last season. We are stuck in a plotline repeat of a Jayme's child being manipulated by evil music biz rivals, Deacon needing anger management, Gunnar and in some kinda love triangle, Scarlett's bad dolly accent impression, and Juliette as the gullible female country John Lennon falling for the latest ist and ism. NO NEW GROUND covered folks. I'll keep watching in case they pull out the ghost of Rayna. The only thing that could save it is if Ian McShane took over the role of Brad. A true soap move that I'd dig.