Some legacy is a trick you taught someone that they now teach without remembering where it came from.

The surest sign that something you passed on took hold is that its origin got lost. Once a method is used with no story attached, it has stopped being yours and become simply how the thing is done, which is the strongest survival available to an idea. Credit and persistence pull against each other here. You can have your name on it, or you can have it outlive you.

Which is reason enough to teach the good trick to anyone who asks, rather than saving it for when it benefits you. Show the shortcut, the grip, the way to word the email. Then forget you were the source.