This is misinformation. Any acoustic engineer will tell you it is only the harmonics, which are the naturally occurring notes in the overtone series, the same ones in brass or wind instruments that are not "clouded with overtones," every closed note is clouded. So unless you're only bowing harmonics this is physically untrue.
Again I disagree, the different tuning systems used in music will alter where the notes fall on the fingerboard. Also, depending on their function in the harmony. Try this with your piano player buddy sometime. Have him play a chord, then tune up a chord tone, say the b in a g chord. Then have him play a c chord and see if you don't alter the note when it functions a Major 7th. Then an E chord then a B chord, and so on and so forth.
While I agree that practicing arco can bring faster results in your style of music, if you are playing pizz it is equally important. If you're playing only pizz styles it is more important. It makes no sense to spend 95% of your time playing arco and then try to blow a pizz solo over Giant Steps at 305 bpm. Intonation comes from big ears ready to listen, understanding of your function in the harmony and your willingness to be flexible to the music. Not a stick with hair on it. Dogmatic opinions only put a strangle hold on music. Even if its so called free music. My 2 ¢
There is lots of hair-splitting that can be done but part of the assumption is that most students with a jazz interest are going to spend lots of time playing pizz no matter what is said!
Prior experience is also a big thing, for example Chris spent a lot of time as a pianist which was obviously huge for the ears seems to be central to his approach.
As far as the fundamental/harmonics explaination I obviouly understand only harmonics are pure tones - I was just trying to condense it without consulting my Hemholz book!