By week 8 they were consistently in the top 5 and by week 12 (in mid-November) they were ranked #1, where they remained for the rest of the season (another 3+ weeks). And it has been brought up many times, but Washington (a team that many people claim to be the "real" champion) was offered the chance to play BYU in the bowl, but they declined (as did other schools).

The argument that BYU's 1984 championship was "mythical" or "undeserved" is actually very weak; can you imagine proposing that a team that was ranked #1 for the last 3 weeks of the season and won their bowl game and was ranked #1 in the final poll as well was somehow controversial? The pollsters didn't have to rank BYU #1, but they did. "But they played nobody!" They were still ranked #1, and obviously the pollsters already take strength of schedule into their ranking decisions, or else BYU would have been ranked #1 earlier in the season (hence that sometimes teams with a loss are often ranked very high, sometimes even #1 or #2). BYU also had more than double the #1 votes than any other team, so it's not like it was very controversial (not unanimous among individual voters, but certainly an big majority consensus of the individual voters and it was a unanimous consensus of the major polling organizations). Ironically, he is claiming BYU's championship to be controversial and fake while saying Utah deserved the 2008 championship, which would have been a much more controversial take given the polls.