As usual, click on the picture to see a larger version thereof. At first glance, the elevation graph seems to confirm that pressing a button on the 62s causes altitude spikes to be registered. Well, first, this is untouched data, as displayed by TopoFusionPro. At the start, I know I did set the tracking to be on, so I did press buttons and there is a slight, 10ft, loss of altitude whereas I'm in the parking lot. I don't know what caused the next two humps and depression between them but I did touch buttons around the 1.0 mark and the change there is not spectacular. I can't find a reason for any other spikes but the last one, when I was saving my track. 20 ft difference or so, I just eyeballed it, did not look at the actual track elevation numbers.
Do I want Garmin to look into it, perhaps fix it? Of course. But does it really matter to me for Search and Rescue purposes? Frankly, without others talking about it, I would not have noticed it, as I rarely even look at altitude. I rarely, if ever reset the barometer as altitude is of little consequence to me. My legs are good at telling me whether I'm going up or down and I can read the map (on the GPS or on paper).
The GPS graph shows altitudes between 320 to 370 ft, quite acceptable for my use.