ubiquitin: I’m sorry but you are simply incorrect. Premises B and C dictate premise A without your addition. Premise A, all Jews must do all mitzvohs. Objection of Gitten and Yibud are fallicious, for Gitten is a mitzvah only if a divorce is needed. So to Yibbum or Chalitzah are circumstantial mitzvohs, as is tzitzis (if a beged of four corners is worn) Every circumstantial mitzvah is a mitzvah if and only if the circumstances call for it.
Premise A in regards to Gitten would be such: Premise B, Gitten is a mitzvah ‘when it is needed’ (otherwise it is not a mitzvah). so if a get is needed it is a mizvah other wise it is not. Therefore your objections are as wrong as can be.
As to archaeology, it is only used as a snif for techelis, the simanei chazal and testimony of the gentiles are the actual arguments.
in conclusion: spreadthetruth is correct, whilst your wrong.