I know a couple of experienced stalkers who have talked about having limited success with an elk cow call on reds..

From what I recall of the conversation, it works best in woodlands rather than on the open hill and also there was no really consensus as to whether the hind was responding to the calf bleat, or whether it was just curiosity..

A "Hind in Heat" scent would be an interesting thing to try during the Rut...