re: 1991 Washington Redskins is the best pro football team of all-time

Before the BCS existed, there was a concept called consensus national champion which therefore determined the national champion. A system like the BCS or playoff didn't exist then, so the recognized adjudicators of the championship were those entities until a more computerized system was implemented to resolve any controversies the dissenting public may present and therefore appease those who took exception to it. Thus, it evolved to the playoff and so on and so forth.