Talmudic discussions are filled with counter opinions from many Rabbanim. In a mishnah there may be several Rabbinic opinions on a specific halacha. After a psak is decided did the minority have to follow the majority le'maaseh? Is there a difference when the halacha is in favour of a 'group' e.g. Beit Hillel/Shammai, the 'school of X' or the 'Rabbanan'? i.e. I assume that, although their positions vary greatly, Beit Shammai and Beit Hillel actually practiced as their 'school of thought' taught.