My questions is this: if a guitar is spot on in-tune in open, 12th fret pressed and the 12th fret harmonic, isn't the guitar supposedly intonated? I mean you can do all the measurements you want but IMHO "sounds good" is still better than "measured right". All the internets site I've researched in have defined a perfectly intonated guitar as having the same note in the open, 12th fret pressed and the harmonics at the 12th fret.
basing on physics, i presume that its more accurate to have intonation based on measurements rather that ear. medyo touchy kasi kung tenga ang pag-uusapan. lets say, i intonate my guitar then someone tries to check the intonation and according to his own ear, its not intonated.
if we based it on measurements, we're following a set of intonation rules here which is based on the scale of the guitar. i would also presume that this is agreed upon by many guitar experts. kung baga, we're following a set of standard common to all.
for me, jun's approach of intonation is not just tuning your 12th fret with 12th harmonic. aside from it, he considers the guitar's scale, the bridge and nut placement/location, and how the frets are placed correctly on the fretboard - that is, he looks over the entire guitar for proper intonation. that is, the 1st fret should be "this" inches from the nut, etc...
he even quoted me on my washburn xb120 that minority of the frets it has poor intonation some frets because the some of the fret wires were put at a wrong place, making a little deviation from the scale. to push it further, he proved it to me by demonstrating and i did really hear with my own ears what he's saying.
from that point of view, if a person is trying to prove something on words, then, he must show it by action. maybe this is the reason why i believe jun's work, he's honest enough to tell you what needs to be corrected and when you get your guitar back, you'll see the difference on what it was before. although he's not perfect, but hey he's willing to correct what he has repaired that you're not satisfied just like what sir al said