Since Pooch passed away, I've only seen one bear bping and it was at the TH by Mammoth. All others that Pooch and I came across took off, whether a single bear or sow with cubs. They may not be able to pick you out at a short distance, but if you move they can zero in on you, found that out on a overnighter close to home in the Buck's Lake Wilderness along the PCT. Mom chased the cubs up a tree and was looking for the sound of us, as soon as I moved she looked right at us and all I did was shift my weight from one foot to the other.