Hi Joe...good question on luring! While luring is usually the least favorite method of clicker trainers, there are still times it's useful. While you certainly can shape a dog to do the dogwalk, and indeed many of us do, it's not a particularly good method for a class, because it generally takes a long time for a dog to be shaped to do it. Many dogs in a class setting wouldn't ever go over it at all, as shaping is often best done at home when you can give the dog several short sessions every day. Once a week just isn't going to work. Luring is often a good way to introduce the dog to the dogwalk, just to get them comfortable with the idea of even going over it at all. It lets the handlers and dogs have some success and many dogs once they get their footing after going over it a few times will happily do it afterwards without a lure. Another popular method is back-chaining, where you pick the dog up or use the pause table placed next to it to have the dog just do the exit plank, about halfway down. When they are happily doing that, you can back up and have them do 3/4 of the down plank. Then the entire plank. And then so on until you are all the way back at the start.
Hope that helps!