I once knew a creative team where the CW was a little more adored and befriended by agency leadership than the AD. Not sure why. Just the way it was. (It wasn't me, by the way.)
At one point, the AD was frustrated enough with the situation to talk to our ECD about it. Hoping to convey her neglected value, she even said, "That [redacted] campaign we just did? [It had just appeared in Archive.] That was all my idea! I did the whole thing - he just changed one word in the tag!"
The reason I know she said that was because within a week, almost everyone in the creative department knew she had said it. That she would claim sole authorship on some work, however accurate, seemed, as one coworker put it, "so unprofessional."
A couple morals to this story:
1. I have never heard a story about a creative who complained about anything to an ECD to their benefit. Complaining just doesn't get you anywhere. Not even when it's about your clients.
2. You can create an entire campaign on your own. But if you're part of a team, you did the work as a team. A little humility is a good thing. (And if your partner's not doing his or her share, it will show. You don't have to put up any red flags. Your CDs are probably more aware than you know.)