I let my DW think she is helping me into a back in site. My lesson learned for this is two small dents on the LH rear fender of my truck, incurred at a CG outside of Santa Fe. She was carefully watching and not in sight in my RH mirror, and forgetting that there was a tree in the way. Should I have seen that tree - probably but until she 'disappeared' we were doing just fine. Now, whether she knows it or not, her main role is to make sure that I don't back into something ---- again. Those dents, left as a reminder for a year but I'll fix 'em in a couple weeks since we now have, TA DA and drum roll, Walkie Talkies