[nerdponx]

Is this a communication issue?

When you realized the codebase was a mess and that it would take you forever to reach productivity, did you reach out to the manager and explain the situation? Did you push back on splitting up the teams, and explain why splitting the teams would be a bad idea? Etc.

Unless a manager is truly incompetent, in my experience they usually listen to technical people when they speak up on these kinds of topics.

[pavel_lishin]

Competence is a spectrum. I've worked with managers who would listen, and nod along to problems I was pointing out, and after the meeting nothing would change.

[craigzucchini]

It's very much a communication issue, but also an incompetance political game playing issue. To answer your question, I put a ton of energy into doing exactly what you suggest, which most people didn't and don't. It ammounted to some changes eventually taking place after I left, according to my former team members, but the managerial nonsense never dissapeared; those managers involved were later promoted.