If you're doing a mojo hand for someone else, but you're holding onto it for her, is it okay for it to be seen on your altar? How does that work? Is it really important to not have the hand been seen or is it more that it shouldn't be touched by others?
I have never had a problem with a mojo being seen or touched. Some workers follow those rules, and have their reasons. I have never felt that kind of sacrosanct treatment was necessary.