I just tried this, and the opt-in message didn't include the name I gave (so no possibility of a blank message.) It did everything else mentioned in the parent.

I just tried this, and the opt-in message didn't include the name I gave (so no possibility of a blank message.) It did everything else mentioned in the parent. The opt-in message did provide an option to text "STOP", so someone really on the lookout for this service could potentially stop tracking with this specific method. Still an excellent reminder of how much information we share.