Maybe I have misunderstood its application. I had assumed it would give a bigger intonation tweaking window.
I originally assumed the same when I first heard of Earvana 'bout 6 years ago (?)...and I was quite stoked, since I always hated the whole G-string transition. When I spoke with the inventor, and I explained to him what exactly I was trying to fix and would it improve things the entire neck and the G-string shortcomings...
..he kinda' paused, and then said something like, "no tuning system is going to fix everything"
...and then went on to promote how much of an improvement if provided in the first 5 frets and he specifically talked about the transitions from fretted to open chords in that area.
The Buzz system works in a somewhat similar fashion, but it only pushed the nut closer to the first fret (same as the Earvana), but it doesn't compensate for individual strings at the nut, rather it does it with a proprietary saddle/bridge setup...which IMO is a PITA, 'cuz every time you adjust, you have to reset the bridge that proprietary system. There are tuners (dare I say it
strobe tuners) that have the Buzz tuning in their prgramming...but you still need their nut.
I do it a rather straightforward way....I set my intonation using the fundamental & 12th fret harmonic...
...with my trusty
Peterson Strobe Tuner 
...
...then I'll tune the guitar while *pressing* each string at the 7th fret, which is basically the low point (bow) of your truss rod/neck adjustment. I don't play a lot of open strings...so that's why I tune only by pressing them, and I press them mid-strength as to how I would normally play them...that way if I'm a little light or heavy fingered at times, it's "in the ballpark".
The 7th fret thing works pretty good since it's the midpoint of the typical playing zone. At the nut where the strings are somewhat closer, it's a touch flat, but that's OK with the lower note range, and its a touch sharp past the 12th fret with the slightly higher string action there, but that too is OK since sharpness is less noticeable in the higher note range.
The idea fort this tuning approach came to me from thinking about how a piano is tuned....on pitch at the middle octaves, flatter at lower octaves and sharper at the higher octaves.
It always sound good and only the infamous G-string needs to be "worked" when transitioning from leads to chords...but I'll tune it just a tiny pinch flat, so full Barre chords sound great, and then when I play leads, I just press it a touch harder or bend as needed to sharp it back to proper tune...or I sometimes I'll touch up the tuning as play...
...and, all of that is always right on the money with 440Hz refernce...
...thanks to my trusty
Peterson Strobe Tuner.
I've tired a few of the
"hit the 4th string harmonic at the 12th, then press the 2nd at the 3rd" systems...and they are all still pretty sour, because they always mixe open and pressed notes. Since I play 95% pressed notes, my way seesm to be more in-tune up/down the neck all the time.
