To many voters, the HOF is the Hall of Guys Who Were Really Good For a Long Time, Even If They Were Never Truly Great.
Terrell Davis, however, was on the short list of the very best players in the NFL; he just wasn't there for very long. But he is still, without a doubt, the greatest postseason runner in NFL history, and that should count for a lot.
If the HOF is about greatness, and the players without whom the story of the NFL cannot be told, then Terrell Davis is a shoo-in.
He was the best player on two Super Bowl-winning teams, and of those who are eligible, is probably the only such player not in the Hall. He was league MVP. He was Super Bowl MVP. He was the fourth player in history to top 2,000 yards in a single season, and he did it despite being rested for eight full quarters.
Here's his career playoff log, via PFR:
That's 1,140 yards and 12 touchdowns in eight single elimination playoff games, which averages out to 142.5 yards and 1.5 touchdowns.
For comparison's sake, Emmitt Smith played in 17 postseason games, and he had more than 142.5 yards in just one of them. Granted, he only had 25 or more carries four times to Davis's six, and therein may lie a hint to why Davis's career was as brief as it was. Anyway, Emmitt averaged 93.3 yards, or 113.4 yards if we include receiving numbers.
Franco Harris played in 19 postseason games, and is second only to Smith on the all-time playoff rushing yardage list. He topped 142.5 yards just twice, and his average over those 19 games was a mere 81.9 yards. In fairness, his significant contributions as a receiver boost him to 108.4 yards per game, which is pretty close to Smith's average.
TD wasn't as much a part of the passing game as Smith or Harris, but even still, his 158.9-yard average is in another stratosphere.
Of the guys who suited up for more than just a few playoff games, John Riggins comes closest to Davis, with 115.7 yards from scrimmage per game. By higher math, that's 44.2 yards shy.
The thing is, of course, that Smith, Harris, and Riggins were all inducted to the HOF within their first two years of eligibility (Smith and Harris made it on the first ballot). These guys are on everyone's short list for the best running backs in the history of the universe, as well they should be.
They are also, arguably, the three best postseason running backs in NFL history not named Terrell Davis. But by comparison, they almost kind of sucked.
That, on its own, should be enough of a reason to make Terrell Davis a Pro Football Hall of Famer.