If X is similar to Y in Z, then it is possible that X and Y came from similar origins. Not definite, but most definitely possible. It is a theory which holds a good amount of credibility, but is by no means certain. -ME
I already pointed out that this is a fallacy in logic (law of the excluded middle). -YOU AGAIN
Back to the present. Watch how silly your statements are. Twins are born X and Y. They have similarities which are undeniable and it can be assumed, argued, or proven even that they came from similar, if not THE SAME origins. You are making the absurd point that using similarities in physical attributes cannot be used as evidence of the similarity of origins. I understand that it is not a statement of fact and is not proof in and of itself, but it leads to possibilities that warrant further investigation and research.
Or use a certain geological area which is heavy in an element. Heavier than any area in the world. Two rocks are found that contain a very high concentration of this same element. Concentrations this high are seen in very few places. It can be reasoned, but not singularly proven from this evidence, that there is a possiblity that these rocks came from the original location that I spoke of. Further research would obviously be required, but it is a clue. A logical flow. You are saying that this logic you have disproven and I am saying this is logic that cannot be refuted. Similar attributes can indeed imply (but does not necessitate) similar origins.
If this were true, I might start listening, however, this statement is a figment of your imagination and is without even a shred of evidence.