(sigh) Let's try again.
Communication is the main task (and, IMHO, should be the sole one) of managers.
No. I mean exactly what I said.
Budgeting, staffing, scheduling, planning, negotiating and a lot more must be done by people that knows exactly the consequences of their decisions. If the guy that does this all effectively has the skills to do that correctly, the guy's skills shouldn't be being wasted on non productive tasks. This guy should be doing active development!
You mean except for budgeting, staffing, scheduling, conflict resolution, planning, reporting, coaching, motivating, forecasting, negotiating, delegating, and the thousand other things a manager actually has to do in the real world?
If you think communication is the only thing a manager should have to do you are pretty clueless about what it takes to manage a group of people. Effective management is a hell of a lot more than just "communication".
If you think that MANAGEMENT should do anything else, you are delusional or you make money convincing people otherwise. :-)
Managers should MANAGE. Nothing more.
Managers don't take decisions. Managers manage the decision taking.
Managers don't do budgeting. Managers manage the budgeting process.
Managers don't plan. Managers manage the planning process.
Managers don't solve conflicts. Managers manage the conflict solving process.
And so on.
Reporting, coaching, etc are COMMUNICATION tasks - where Managers should excel.