Jurassic Referee wrote Maybe you can get away with stuff like this in low-level rec league games with daddy-coaches, but I'd be awful careful of trying it at any higher levels. And if you do, you'd better know your audience.
Agreed. Keep yourself amused by keeping such comments in your head. The situation is better served with a respectful explanation than a comeback. You'll be better appreciated for it, too.
Besides, since this coach was operating on a rules myth, it's likely he's been teaching his kids this same myth, and he may have developed a strategy around it. ("If Johnny can't get the ball in-bounds to you, get out of bounds. You'll have five seconds, too.") We've all had moments where we were dead wrong about a rule myth. It's better to coax someone out of the myth than to yank them.