I'm not actually sure I have ever known anyone to use a tuner like this, Colin. Part of learning a string instrument is learning intonation by ears. String players have to be able to do this all the time - in fact, you often have to play slightly wrong, to sound right. You tune the open strings so they are dead right, then you pitch by ear to these. The usual thing is you actually put your finger down slightly wrong, and your ear shoves your finger up or down a bit. I'm not sure the tuner is the right way to learn - what happens when you don't have it, or the battery goes flat. You really need to train your ear the way people had to when tuners had not been invented. In fact, apart from the few folk who have perfect pitch, most people don't play in tune, they play with relative tuning, like guitar players do who tune by ear. You start with the E or whatever, and tune the A to it, then the D and so on. You strum a chord and then make little adjustments till it is right. The E could have been an F, or even half way between E or F - it doesn't really matter. You probably could use the tuner to get the bottom string accurate, then as the Perfect 5th above has a nice beat, you tune that, then move up a string.
I know you are inventing your own system Colin - but theres a chance that when you get quite good, it falls down because you left your ears behind. My double bass might be tuned to E, but probably isn't - because I don't have a tuner - I just play in tune because I can hear flat or sharp, and can correct very quickly. ANY fretless instrument needs the player to develop their ears at the same time as their fingers. It is probably the absolutely essential feature. I'm not saying they're bad, but they are meant for tuning the open strings - so before you start practice, and maybe during if the thing goes out of tune. Not for intonation. That's why the battery save feature never even gets a mention - nobody expects them to stay on?
