I think the coupler is hard for some dogs to get used to, but once they master it, it really is quite nice. I switch it up. I'f I'm going for a leisurely walk, no time frame, where I want them to stop and smell the flowers and I'm allowing the guys to lift their lets on everything in sight, then I take them on seperate leashes, they are trained to walk at my heel unless I release them (command) to go. The coupler I use in the morning walks before work because I am on more of a time schedule and then I throw in my Golden as well. Its a sight. My golden is on a leash tied to my belt, she is trained to heel and is awesome at it, then I put the little ones on the coupler and off we go at a good clip. It took awhile for them to get used to it as Cooper (being older) was pulling, and Bentley the yonger lagging behind, eventually with a little short practice runs they got it down. Every now and again, someone is pulling more then I'd like so I stop (in my tracks), they look at me and we regroup...I agree with another poster to make sure they can walk nice on seperate leashes and then gradually try and introduce the coupler and let both dogs know its ok. I try to also make sure that no one is in the front that both dogs are at equal length. good Luck
Kathy