They work fine on my dimi! I like to use the triads starting on the 3rd and higher notes of the chord, not the root.
I suppose in a sence they work better on dimi than on solo since they can be narrowed down to three patterns, it's just that I've been practicing certain patterns that appealed to me, and I just couldn't make it work all that well.
For instance I liked to play up one triad and down another for instance 135 on D and up to 1 in C then down 153 in C
That is to say up: d f# a and down: c g eb
These kind of patterns in all inversions appealed to me, but didn't work so well though.
I must be honest, I haven't actually watched his triad master class, I just looked triad pairs up on youtube...
Does he mention the kind of triad pairs I talked about, and does he relate triads to hexatonic scales?