I'm gonna say something unpopular: I don't like to rush.

[Vahlnir]

Actually, no. A tank refusing to pull mobs off someone is them refusing to do their job and endangering the run. Those mobs will eventually target someone else if you let them purposely ignore them, and if it happens to be the healer (or the healer is who you let die). You've now made things worse out of pettiness. Someone pulling ahead of you isn't doing it to show you up but to speed things along. Now you may dislike that, and can certainly voiced such afterwards. But there's no way around you're just being petty.

I'm above letting people die, but I'm not above giving them a scare. I totally plan to save someone who pulled for me...but only after they've taken some damage themselves. Usually that puts a stop to it without ever having to say a word and without slowing things down. Straight up letting people die though because of this is indeed petty.