Testing Manager - you manage the subproject that provides testing service, not the development project

The testing effort is a sub-project of the overall project. You apply resources and deliver services. You have a lot of control over how the testing project is run, and you should choose your style as carefully as you might wish the project manager had chosen his.

Somtimes project managers make mistakes, and sometimes they can benefit from your advice. By all means, offer it. Speak your mind. But the final decision on how to run the project is the project manager's. If he doesn't take your advice, so be it.

I don't want to write much in this post about the human issues involved in managing people under stress. For now, we'll note that when project managers and executives make bad decisions, they sometimes subject testers to verbal abuse, demands for excessive overtime, and demands to compromise their integrity. This is not within the project manager's reasonable scope of authority. As a test manager, an important part of your job is to protect your staff from abuse.