In the band I play in we usually all tune to the piano/keyboard before playing. And sometimes we do use a tuner for the reference. The main idea is to get everyone tuned to exactly the same pitch. Now I don't have anything against guitar tuners. My main beef with them is that there isn't any guitar that I know of that has perfect intonation. Maybe they would with a Buzz Feiten fret setup, but I don't own any Buzz Feiten guitars. So after using a digital tuner, I always end up tweaking the guitar so it sounds sweet everywhere on the fretboard. To me that somewhat reduces the usefulness of the digital tuner.
Well, we don't have a piano player (all stringed instruments) and we really bang on the strings and use the (horrible Jazzmaster/Jaguar) trem so one of us could be flat, the other sharp, and none of the strings in tune so unless the entire band has perfect pitch (I just have sort of close relative pitch) and can tune without having to hear the notes (in silence) we lean on the crutch of a digital tuner on stage pretty heavily.
PERFECT intonation is undesirable because of the overtones with chords. The best method is to use a VERY ACCURATE tuner (like the Strobostomp or equivalent
) and adjust the bridge intonation so the guitar is in tune for your brand and gauge of strings. Next would be to tune up with a "sweetened" tuning like you said so that it sounds good everywhere on the fretboard...and guess what...the PETERSON tuners also have built in "sweetened" tunings that are "off" just a little bit that sound great...and you need a tuner that's accurate in order to be able to do that level of fine tuning.
Lastly, the Earvana nuts really help (and are much less expensive than the Buzz Feiten system).
Just my biased opinion after owning the Strobostomp and Earvana equipped guitars.