Tactful ways to inform people that they're playing badly?

[Hash_Browns]

If I've offered advice, I always make sure to ask if they want any first. If they say nope, I'm good, then that's it. But I don't often really ask. This isn't school. I'm not their teacher. I have no idea why people think they can dictate stuff to random people in a dungeon and it's not rude as hell.

Say you're standing outside tying you shoes and someone comes up with "Hey, want some advice on how to tie your shoes?" "No, I'm good" "But you could do that so much more efficiently!" "I'm fine" "You just don't want to learn how to tie your shoes PROPERLY!"

You wouldn't do it in real life. Don't do it with the anonymity of the internet. If it's something you just can't stand, initiate a vote dismiss if they're being disruptive to the party, or take the penalty and remove yourself. It's a PUG. You will probably never see these people again and why start drama when there doesn't need to be any? The only person you can control in life is yourself.

Except you tying your shoes has nothing to do with a group effort where someone is clearly not carrying their weight. When advice is offered is usually because you're making someone elses job on the team harder.