One of the things I enjoyed being guest photographer is being able to capture scenes while the OP is posing and conducting and reposing, and posing again....
My trusty d600 sometime I just wanna use 50mm for all parts of the wedding, but there were times I need wider angle. so next setup this pair ( 28mm/50mm) would do ( atleast for most event). my 70-200mm and 35mm are always ready, closeby.