> and promoted those who could argue against him.

I've worked with managers like this, and although it might work for some, it was hell for me. Having to constantly argue to defend your ideas is draining, soul destroying, depressing, and lead to me burning out multiple times. Discussing and critiquing ideas should not involve force from either the idea's champion, nor who they are pitching it to. If, at the end of the day, you're evaluating ideas based on the force by which they're presented all you end up with is ideas that support being presented and defended forcefully - not deftly, nor intelligently.