Of course, the ultimate pesak is not bound to the peshat of any one Amora, even when we decide according to his view. A sugya can combine the views of one Amora with the principles of another in order to apply the halakhah in question to various situations. It is up to the poskei ha-dor to determine the relevant halakhah for their time. That is why halakhah ke-batra’ei, the halakhah follows the later opinion (within the limits of Masorah, of course). But if Talmud Torah is pursued with the proper derekh, or, more precisely, with one or more of the proper derakhim, then, as Rav Hutner זצוק”ל pointed out, the result is “a positive creation of new Torah values.”
Yaakov Elman, “Rava as Mara de-Atra in Mahoza”, Hakirah 11 (Spring 2011), 64-65.