Our dog is a mutt with Australian Shepherd, Husky, ??? in him. Pretty smart dog. Back in college my roomate had a mutt (part Australian Shepherd) that was REALLY smart. You could be in the front yard and tell it to do in the huge backyard and “get your stick”. It would come back with the stick and play. Then “go get your ball”, go get your frissbee, go get your rope, etc.
Also, the only strangers that he would bark at when they came to the door were the Jehovahs Witnesses and the Mormons, and it sounded like he was trying to get them through the door. Mail man, repair guy, friends, etc. no barking (he didn’t bark much actually). Weirdest thing!