I think it also depends on the number of laying chickens you have, the activity in the boxes, etc. I think if there is more activity in the boxes, and as others have noted, other chickens with poop and stuff on their feet inadvertently tracking that stuff into the nest and onto teh eggs, if you have large numbers of eggs you are selling/giving away or even consuming yourselves, I would think the recommended washing/cleaning procedures would be a good idea.
For a small backyard mini-flock such as my own (6 chooks, all girls), we get at most 2 eggs a day. We retrieve them from the nests within half an hour of so of being laid (only once have we left them in there for a few hours when we were not at home), and the worst it ever gets is a little streaky. I brush off the poop, but there is almost never anything at all visible on the outside of our eggs, and leave the eggs intact and covered in the fridge. When it comes time to eat them, I thoroughly wash them and let them sit a few minutes before I cook them. Even with store-bought eggs, my mom and grandmother always taught me to wash eggs from the carton before you use them anyway because people open the cartons to see if any are broken & a lot of people run their hands across the eggs in the carton. You don't know what kind of stuff is on them, so you wash them anyway.
So I guess the simple answer is that there is no simple answer--do what seems right to you and your flock/situation. How's that for noncommittal but sage advice? Lol.