I've been thinking about this and that would have had to been one of the toughest times to win a division ever in the league.
Not just the Steelers were great those years (Winning two Super Bowls and being the team to beat)
You have the "Luv Ya Blue" Oilers who appeared in two straight AFC title games led by Earl Campbell and coached by Bum Phillips
The Bengals while sort of finishing near the bottom normally of the division actually made the Super Bowl with Ken Anderson at QB and Forrest Gregg at QB, and were one 4th down stand away from winning a Super Bowl.
And then the "Kardiac Kid" Browns of course, Led by Brian Sipe and Coach Sam suprising many and taking the division in 1980, always winning (and losing) when it came down to the wire, if not for an interception with less than a minute to go may have won the Super Bowl.
Even the league MVP's during that period seem to reflect how good the division was:
1978 Terry Bradshaw Pittsburgh Steelers Quarterback
1979 Earl Campbell Houston Oilers Running back
1980 Brian Sipe Cleveland Browns Quarterback
1981 Ken Anderson Cincinnati Bengals Quarterback
On a related note I sort of wish that the Oilers and my Browns had never moved so we could have preserved this great division alive :(.