It should be noted that Holdsworth actually played a bit of violin (you can hear it on Temporary Fault off I.O.U.; Karzie Key off the infamous Velvet Darkness album; and recordings of Tempest, Soft Machine, w/ Gordon Beck, and Gong).
Holdsworth even experimented with fifths tuning on his SynthAxe (since you could just do that in software), most notably for the song Non Brewed Condiment[1] off Atavachron, and the solo in In the Mystery, I believe, and had a separately tuned guitar for the live performance of the aforementioned song[2].
There's an interview from the 90s where he talks about his thoughts on fourths vs fifths[3].
He later said at a clinic (in the 2000s) that if he were to relearn the guitar, he would've used all-fourths tuning[4].
[1] https://www.youtube.com/watch?v=1yTCQ1-GzIg
[2] https://www.youtube.com/watch?v=qO3o484Z2OU
x x x x
x x x x
x x x x
The major third between the G - B strings in standard tuning provides relief from the diagonal x x x x
x x x x } maj 3rd
x x x x }
x x x x
...
It seems like chromatic runs would be a source of difficulty for the violinist tuning in standard fifths.