Basic 3-seconds question

[Shogun]

I'm asking this for a coach friend who'd like to know the rule so he doesn't mislead his kids...

I understand that there will be situational variations that can be complex... but the basic question is, what do you need to do to reset the clock (or to avoid committing a 3 seconds violation)? Let's assume you're gaining a substantial advantage from your position. How much of you, technically, needs to be OUTSIDE the key to be safe? All of you? And is the line part of the key?

From Dan_ref's and rpirtle's replies (thx, btw), it's clear there's a lot of judgment involved. I'm hoping someone can distill it down to something simpler... something along the lines of this (which I just now made up and I'm sure is completely wrong, but was fun to write): "Technically, if one toe is on the line, you're 'in the key'... but you won't get called unless you're 1) gaining advantage and 2) at least half of you is in the key." Or something like that. Any takers?

Thx.

[Edited by Shogun on Dec 10th, 2002 at 12:06 AM]