[Ref in PA]

Would you have called this a technical foul before the penalty change this year? If so, then call the violation. If not then let it go.

For me personally, I think the rule (although it is not specific) applies to live balls in bounds. Restrictions have been outlined for throw-in plays by rule and they allow offense players to voluntarily go oob along the end line - they don't specify the reason, just that it is okay. By the same token the restriction is different for a defensive player with different penalties. Because the play is specifically covered in the rule book as being allowable during a throw-in, I do not think 9-3-2 is intended to cover this.