hahaha yes I can see that now! And I can see now that ZED.CWT's comment below was getting at the same thing, I just didn't understand it at the time. This is the most fascinating thing about writing katas, to be honest: figuring out how to translate your ideas into instructions that actually make sense to anybody else ;)

Yes thats the intutive way

Ohhhhhhhhh so they're finding the point where half the mass is on one side of the stick and the other half is on the other side of the stick, but not taking into account the distribution of that mass -- finally, thank you, I think I understand the situation now & what I need to illustrate.

Pretty much the summing of two halves I guess and not calculating the COM

Thanks! Have added your suggested alterations. But I'm still confused what the non-physical interpretation people are having is: can you explain? It seems very common but nobody will tell me what they thought the problem meant