[eowyn]

>These people will be very persuasive - it’s their job! - but they won’t be there during your next promo discussion, and they’ll walk away from you the second it’s in their interest to do so

While I agree you don't want to be helpful at the expense of your role and definitely want to keep your manager in the loop, it can pay off to become useful to senior managers outside your org chart. With more companies including calibration-style conversations in performance reviews, often those managers will speak up in cross-team calibration conversations to plus-one your performance review. It's way more persuasive when they say you were useful vs your own manager going to bat for you.