The 180 thing works on some dogs. Not with my Aussie. He wanted to go places - he didn’t care much where. So if he pulled and I did that maneuver, he just pulled in the opposite direction! Just stopping dead worked best for him, but it took a while…
I dont care about prong collars- not because they dont work, but most people are not trained to use them. I’ve been in rescue and training for 40 years now and when I get a dog in that has issues and likes to pull- and those are 90% of them - a “choke” collar works well- if used right. It used to be called “training collar”, but they forgot to train the handler 
If yours doesnt pull because you are speed walking, then you are being effectively trained by your dog 
and its now a game of who can walk faster… turn into a OLD person- walk slowly, deliberately. Make him slow down, pay attention and lay down flat on command. I just got a 8 month old border collie pup in 2 1/2 weeks back- poor pup had never seen lifestock , but came from working lines - she needed a home, I needed a working dog for herding- so the training is on. I gave her 3 days to stop shivering she now flattens on command- on any gate and door. She sits and comes on command. We are still working on the coming solid ALL the time, but she is having fun and she is young- she will get it in the next 2-3 month. She is listening around the chickens- huge plus. And - she doesnt pull. She stays just behind me and watches whatever I do. Took a moment for her to grasp that, but she is good. We have other dogs- they get to listen as well but this one is being trained for the sole reason of herding sheep or goats the main goal is that you set the rules- you decide how fast or slow you walk, you decide when to start walking and when to stop. Make it a game- they love you for it and are more eager to learn
