And yet you wrote about grandparents before I even knew about this thread.
a) No I didn't.
b) So what? We were still discussing a very specific person, i.e. Kos88.
A person born outside Poland has to claim the Polish citizenship and the decision has to be made.
Again, that is completely untrue. Google the phrase "passport trap" for details.
the source is a site run by Polish lawyers in Poland.
Marvellous. This source legislationline.org/documents/id/4332 is the Law on Citizenship (1962, as amended 2007). "SECTION 2 - ACQUISITION OF POLISH CITIZENSHIP
Art. 4. The acquisition of Polish citizenship by birth occurs when:
1) both parents are Polish citizens, or
2) when only one of them is a Polish citizen and the other is unknown or his/her citizenship is undetermined or he/she has no citizenship.
Art. 5. When both parents are unknown or their citizenship is undetermined, or they have no citizenship, their child shall acquire Polish citizenship only if it is born or was found on Polish territory.
Art. 6. 1. The child of parents, one of whom is a Polish citizen and the other a citizen of another state, acquires Polish citizenship by birth. However the parents can, within three months from the child's birth, submit to a competent authority their concordant declaration stating that they choose for their child the citizenship of the foreign state of which one of the parents is a citizen, if under the law of the foreign state, that child will acquire its citizenship."
Note how place of birth is entirely irrelevent to a child born to at least one Polish parent? Looks like you might want to find a new law firm.