I apologise for not providing all the colour information so that you could reproduce my attempt at experimentation. Here are those numbers:
purple: (158, 0, 126) or (.6197, 0, .4141)
orange: (255, 59, 38) or (1, .2313, .1490)
Anti-gammaed (^ 2.2), that would be:
purple: (.3489, 0, .1437)
orange: (1, .0403, .0151)

Adding the colours: (1.3489, .0403, .1588)
Clamping (1, .0403, .1588)

So, Clamp does only bring down to 1 those values that exceed 1 or up to 0 those that are less than 0 of-the-tuple. In which case, I don't want to be wandering into the add-colours-then-clamp zone, since that won't give me a predictable outcome.

Monterey/Mint21.x/Win10 - Blender3.x - PP11.3(cm) - Musescore3.6.2

Wir sind gewohnt, daß die Menschen verhöhnen was sie nicht verstehen
[it is clear that humans have contempt for that which they do not understand] 

Metaphor of Chooks