Walking a dog and potty training often can be two different things for a dog. I don't feel like it's a bad alternative for training, but I do feel like it's not so necessary.
Go to your backyard, (I'm assuming you have one...), and leash the dog. Stand in one spot and just find some words that your dog can get used to as a command to "eliminate". Take treats w/ you... On one spot let your dog walk around you while you say "go potty", or whatever. Do this after a meal, or up to 10 minutes after a meal. Make potty training a designated experience seperate from walks. Eventually the dog will eliminate and then you pat the dog and offer a treat. Make sure you have a tone to your voice that is specifically for when he/she listens to a command. This tone adds to the training reward. Never should it be used otherwise. It usually sounds more high pitched and use words like "good boy" and "YES" nice and loud.
I usually (as a dog trainer) recommend that the handler/owner walks their dog prior to a training session, however walking and territory marking (peeing over another animals urination areas) is not an effective way to teach a dog the potty training command.
Lots of people don't teach this command and that's fine too. You can walk your dog before bed if that's what you choose. I just feel that training a dog to eliminate when YOU CHOOSE makes life a breeze.
I walk all 5 dogs at the same time all throughout a neighborhood and not once do I have to take out a baggy to clean up after my dogs because I've asked them to eliminate BEFORE the walk...so we can enjoy our walk.
...just food for thought.
