I know why one would call Denver a 'bad' team......maybe not 'bad' but suspect at best.
I love the Broncos more then any sports franchise in the world, I've been a huge fan since I was five years old and John Elway became the quarterback, having said that, they were 3-0 last year too and ended up 8-8. Couple years before that they had the greatest defense ever through 4 games (they didn't even make the playoffs that year). The Broncos always start hot and fade.
But you never know, this is a very different Broncos team then in years past so maybe they won't falter down the stretch.
Cowboys on the other hand have so much talent it's sick. If they don't win one in the next couple of years, I look for them to blow up the team and fans will have to endure a very Phoenix Suns like reputation about their team.