Subsequent research showed that yellow / orange colour schemes are not very good at-all for conspicuity. Hence that UK military training aeroplanes are now mostly plain black, as what matters is the colour temperature, not the colour. Basically you want maximum colour temperature difference from the background.
Most airlines understand this - hence mainly white upper bodies, and mainly very dark lower bodies, which tend to give the best possible contrast against most backgrounds, most of the time.
I happened to be involved in specifying the paint job for this aircraft, which was as close to best practice as we could manage whilst maintaining corporate identity, for example...
(Yes, it also has a military HISL and standard strobes.)
Of course, the slightly murky whiteish of a very great many training school aeroplanes is nowhere near best practice.
At risk of stating the obvious - mid air collisions are virtually never caused by aircraft pointed directly at each other, as they are generally aircraft on non-reciprocal but converging courses.
G