I agree, marketing at its best. I don't know if I ever heard it so I'll never say for sure. I did hear a mature buck cruising behind a doe make a very long almost constant growl once. Don't know if that qualifies or not.

Would I ever use it? Nope. I read too many things that make sense toward not using it. If you're in an area where there aren't mature bucks, I'd say 4 1/2 or older, you'll probably spook more deer than attract.

I agree with calls, but not scents. I've had a lot of success with mock scrapes and hanging scents wicks. Is one better than the other? I don't know. But I've had most of my success with one particular brand.