It depends on the situation. Running your call 3 feet off the ground in the middle of a plowed field is definitely going to look suspicious, especially in the daylight. IME, K9s are very aware of something new in their territory.
But if you mix it in with some kind of foliage, it will be fine. I balance getting it off the ground with making sure it doesn't stick out too much. Of course, in the dark, you can get away with more.
