I'm no expert, never have rattled a deer in in my ten or so attempts. But as far as calling I do think less is better. I only call during the rut, I have cold called deer in, grunting and bleating every 30 minutes or so on the stand. There's no magic formula, we've all looked at deer and called to them just to have them pick their heads up to look at you them go back to what they were doing. Same thing happens with deer you can't see. But when everything is right they come in on a string.