As to the tuning and raising thing….yep I do that. But not 2 or 3 feet in the air above the neck of the harp – they must have “go go gadget arms” coz mine aren’t that long…..
It is mostly a habit, but you do try and strike the string quite quickly and firmly when tuning – get a clean and pure sound. If you strike each string differently, with different volume and at a different rate, yes, that will affect how the tuner picks up