Again, not Holdsworth. But I do feel this one is somewhat Holdsworth-adjacent as recently, I've been covering advanced harmony with several different students - lots of big juicy extended chord voicings, deciphering the seemingly indecipherable jazz chords (Cmaj13#11b9, anyone?) and while fun and interesting in it's own right, this has led to some real finger-twisting chord shapes, along with the inevitable question -
"What's the point of these weird chords?"
Now, at this point I could go on a tirade about how knowledge and understanding is it's own reward, how a musician should constantly be striving to push his or her boundaries, how to express themselves with more subtle shades that evoke precisely the right emotion... and to be fair, that's my approach. But, it's not for everyone, and I can appreciate that - it's not my job to force my approach and way of thinking onto a student, it is my job to adapt my approach to theirs so that they can become a better version of themselves, not a clone of me.
So, rant over, what does this mean in practice? Well, let's take the aforementioned Cmaj13#11b9.
The major part tells us to expect R 3 5 7, the 13 to expect 9 11 and 13, the #11 to sharpen the 11 and the b5 to flatten the 5. This means we're dealing with R 3 5 7 b9 #11 13. 7 notes. With the best of intentions, there are (usually) only six strings on the guitar. So, we need to trim the fat.
Do we need the root? Yes (unless we have a handy bass player nearby)
Do we need the 3rd? Yes - it defines major or minor.
Do we need the 5? No, the 5 acts as a filler interval, the same through major, minor and dominant.
Do we need the 7? Yes - it defines major or dominant.
Do we need the b9? Yes, specified within the chord name. Normally we could omit this interval as the presence of higher extensions implies it.
Do we need the #11? Yes - again, specified within the chord name. Normally the presence of the 13 would imply it, however, allowing us to omit.
Do we need the 13? Yes, as the highest extension.
So that's trimmed us down to something that will at least fit on a guitar neck:
R 3 7 b9 #11 13
C E B Db F# A
That said, it's still not exactly something you would consider wieldy. But who says you have to play all of the chord all of the time? Let's look inside this chord:
C E B - Cmaj7 (no 5)
E B Db - E6
B Db F# - Bsus2
Db F# A - F#m (2nd inversion)
F# A C - F# diminished
A C E - Am
Now these (admittedly some more than others) are all fairly usable triads, and played over a C bass (if you haven't got a bass player handy I suggest capo'ing at the third fret and letting the A string ring out as a pedal tone) they will act together to imply this most monstrously lunatic of chords, and you may even find yourself stumbling across a useful riff or two in the process!
(Disclaimer - JM Guitar Tuition is NOT responsible for the loss of whole evenings breaking down bizarre chords in search of your next killer hook...)