I've been told that I sometimes have that effect on people.

If there isn't already, there definitely needs to be a cure for that. This world can't take two of me.
I too believe that this is a violation. I think that it is perfectly legal for the player to go fetch the ball over there, but that he must then return to within the 50 feet behind the end line and make the throw-in from there prior to the five seconds expiring.
No one is going to allow the player to turn the corner and run up the sideline OOB and make the throw-in from within the coaching box, right?

Therefore, the intent of "outside" the end line must be synonymous with "behind".