Although you indicate that you are supposed to tell your manager what you think of him, you are actually going to be giving feedback on specific aspects of his managerial performance. This approach reduces the likelihood of an instant defensive reaction from him, although that is still possible.
Nonetheless, sugarcoating your comments works against your company, your manager, and all of you. When you provide inaccurate information, you are undercutting company efforts to upgrade managerial proficiency, and you are wasting a good deal of time and money as well. Sugarcoating also denies your manager valuable feedback that could help him work more effectively. And, your sugarcoated comments will work against you and your associates because management will assume that your manager is doing a great job. That means that any of the behaviors that are presently sub-par are going to continue and probably worsen.
If your manager engages in retaliatory behavior as a result of your openness, you can expect senior management to engage in its own retaliatory behavior to deal with him.
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