SholomBenYosef
Thanks for providing details. Obviously my general post doesnt necessarily apply to your case (in spite of some forced conclusions drawn by others) You arent really discussing abandoning your family’s mesora, rather are discussing abandoning one adopted by your father.
Though I would like to point out in regards to “but surely the Rashi/Rosh/MahaRam etc knew what they were talking about… ”
Of course they do! However they often argue so how do you decide whom to follow? Which is why MEsora is so important if people are free to choose any conclusion they want based on their own research /whim much of yidishkeit falls apart