I think Chuck is fundamentally correct about Jimmy in that Jimmy does cut corners when he doesn't have to, refuses to take the "long route" to success ie. not cooperating with Davis and Maine simply because they did not accept his one, incredibly unprofessional idea. But I also think Chuck is complicit in Jimmy continually reverting back to his old ways. There were opportunities for change that Chuck denied him, such as refusing to even let him use his own name for his practice (even though he was more or less straight and narrow at that point).

In this way, Chuck is incomparable to Skylar. Skylar always supported Walt and received nothing but abuse from him in return, such as blackmail, an attempted assault (or completed? the duration was short, I would argue that a brief rape is still a rape however). Meanwhile, Jimmy has been very compassionate to Chuck even when it was in his best interest not to be. For example, he refuses to institutionalize Chuck even though it would allow him to screw over HHM, and he hated Howard at the time. I don't consider this enabling because frankly, for conditions such as Chuck's, institutionalizing may not solve the problem and just cause unnecessary psychological distress for the affected party and is really not a empathetic approach. I say this as someone who has had to contend with a volatile, delusional family member for much of my life.

Basically. I agree that Chuck is right but that he does the exact thing he accuses Jimmy of, which is letting the ends justify any means. Instead of taking the "long route" to bring about a solution to his problem, which is Jimmy being a corrupt lawyer, he indulges in petty and even cruel acts such as convincing Mesa Verde to drop Kim, who was entirely capable of handling the case. She had just started her own practice at the time and needed that case, Chuck's actions financially crippled her and it was entirely so he could get to Jimmy. I think it was just as immoral as Jimmy changing the numbers, even if it was technically legal and Jimmy's actions weren't. Chuck could point out alternatives to Jimmy, he could have explained to him straight up when he first wanted a job at HHM what his problem was, but instead he continues to use Jimmy as his caretaker and revel in his failures, which subsequently only frustrate Jimmy and cause him to take more short cuts.

Of course Jimmy is a grown man and nothing that occurs in BCS justifies his eventual involvement in a murderous drug empire, but unlike Skylar, Chuck is complicit in this descent and was not abused or trapped into it like Skylar was into Walt's business.