Training Question - Is this fair?

[Doodlebug]

I am trying to get my dogs to respond EVERY TIME to the word 'come'.

When I call them to come inside sometimes only one of them will obey me. Is it fair to give a treat ONLY to the one that obeyed me? I usually either give both a treat or neither one. I don't know if it would be mean or confusing to them to only give one dog a treat. What do you think?

This is important to me because there is a big dog that lives in the yard behind us. He is very aggressive and agitated and wants to get at my dogs. It's a pit bull and I think he wants to tear them up. He rushes up and down the fence line growling at them and ramming his body into the fence to try to get through it. I am terrified that he will come after them and I need them to come in when that dog is outside.

Thanks

[For My Coby]

In my opinion that's fair. If you are using the treat for the reward to "come" then only the one that comes gets it. Or if the other one comes late, he gets his late. I'd suspect that it would help the other one learn too.

I struggle with treating "come" when I am trying to catch them for something like stealing. I want to reward the "come" but discipline the "theft".