Hi! I've done a lot of dog rescue and so I've lived with lots of different dogs and seen variations in how much they do certain behaviors such as licking, chewing, drinking water even and other habits. I've known several dogs who have licked themselves (specifically the front legs) obscessively due to over-crating and the scars became permanent and ugly. The dog can cause what is called a lick granuloma which can grow really large and it can be really difficult to get them to stop it even when they have licked themselves bloody, so you do want to keep an eye on this. It could just be boredom and you might try chewies or toys. The over-crated dogs were just so bored there was nothing else to do. I've also known some little spitz dogs (poms) that licked their legs until everything turned brown and slimy continually, like a nervous habit. They all needed to be treated medically for this!
Since at this point you are not sure if he is doing this too much or not, he probably just is being overly clean. I agree with the suggestions to clean him yourself. If he continues to lick after he is clean and has chewies to entertain himself, at that point, I'd start working on a command such as "quit" or "enough"......if he won't stop licking. Let him do a normal amount of licking and cleaning when he comes in from outside or is wet and then tell him your command word to cool it now. I would just interfere with the licking if he did not understand the command, such as cover the leg with your hand, or pushing his face away. He sounds smart, so I think he will get the point because the dogs I had did fine learning what "enough!" in an exasperated tone from me meant.
If at any point you get concerned, a really inexpensive thing to try would be to be an e-collar at the feed store and have him wear it for a few days to try and break the habit and heal whatever it making him itchy/licky. With the one dog, I would just pick up the e-collar to put it on and he would stop licking. This dog had huge lick granulomas because he suffered from food and probably flea allergies. If your dog has skin issues and ear infections too you might think about food as being a cause. I'd keep track of the protein you are feeding your dog and not skip around so that you can figure out if your dog has allergies. It takes a whole month or more before the effects of a new food kicks in, so don't change foods every week. Try using a food with an unusual protein base such as duck (not chicken, lamb or beef especially) and stick with it a month and see if that helps. I'd also avoid any dog foods with corn as a main ingredient. I'd also smell his ears and make sure they do not smell yeasty. And finally, if the skin on this dog gets too wet with saliva from too much licking it can create a hot spot. So if at all possible, keep the fur dry.
Hope my perspective helps, but I've dealt with this kind of thing a lot.
