At what point do you step in and offer help?

Interesting, as we do just the opposite! As I am towing a trailer, sometimes I cannot see at all where I need to back in.

My wife positions herself at the rear corner of the site where I can see her, with a radio. If I can't see her, the unit does not move.

She guides me in by radio where she wants the trailer. All directions are orientated to my driving position. (Left means MY left)

She uses commands such as hard left, easy left, slow, Stop.

Works well with us and she guides us to inches of where we decide we want to be when first arriving.

There is probably more than one right way to back in a coach, trailer or fifth. Whatever works for you is the best. I don't like distractions nor do I find it beneficial for somebody standing outside the RV to tell me how/where to drive it. They are not responsible for driving the RV, I am. Spotters for me are eyes and a fixed point to back to. If you turn the mirrors (it helps to have electric adjusting mirrors) it is easier to minimize but not totally eliminate blind spots when backing a trailer/fifth. I never back to a place where I cannot see at least one side and have previously walked and visually checked the blind side. For me the spotter serves two functions: check to make sure I don't hit something (branches, rocks, etc.) and to act like a fixed point to back to. I like the spotter to be on the passenger side (often the blind side)and positioned exactly where I want the rear of the trailer to be. We work that out before backing. She is not driving and does not distract me with 'left' 'right' 'back' 'front' stuff. I can back into a site with or without a spotter. A cone is just as good but, of course, cannot function as extra eyes. If I notice my spotter has lost her focus (talking to others for example) I stop moving until focus is regained. This is not the time to chat with neighbors. If somebody I don't know comes over to help I shut down until they are no longer a factor. I don't want to deal with somebody I don't know and they don't know me. I can usually get into a spot within a minute or two and maybe up to two iterations. I never forget I (not the spotter) am backing the RV. That is my job. If I do a poor backing job it is my responsibility not the spotters. There is no use having 'words' with her as it is not her responsibility to park the RV. We don't argue, blame each other, yell, or any of the ridiculous antics that so often is associated with two people backing an RV that has only one driver. Watching others, it is obvious within a minute or two who has practiced backing and who has not; who has learned to work together as a team and who has not. It is a joy to watch a well executed trailer or fifth enter a site and be parked within a minute or two because they are good at it. There should be pride in a well executed backing job.