Certainly you admit people can confess that Jesus is Lord and still be non-elect. so if you are going to make suppositions about someone's heart contrary to what they say this certainly doesn't 'prove' anything as you initially stated works prove faith.
BTW, were you raised Calvinist? I was. Most Calvinists who fight for it converted to it. Doesn't prove anything but I find it very interesting.
You would have to explain that convoluted belief to me. Are you saying that people who dont claim Jesus as their Lord and Savior still confess Him to be Lord and Savior or are you saying even if someone is non elect (per Calvin) they still claim Jesus as Lord and Savior?