Colonel Reb,
Good points. In fact, my awakening to the racial nature of the NFL actually occurred in 1986. I had already stopped watching the games, for the most part (this was just before fantasy football lured me back in), but decided to tune in to the Super Bowl that January. I was somewhat interested in that game, because it featured two teams that had long been non-chosen, in my view- the Bears and Patriots. I was especially intrigued by the Patriots, as I used to root for them when Plunkett was their starter and was throwing to Randy Vataha, one of my favorites, and Russ Francis. I also knew they had a white starting RB, Craig James, and that was already a real rarity in the NFL (it was also the last time a Super Bowl team had a starting RB who was white). Anyway, when they introduced the starting lineups, the Patriots chose to introduce their defense. The Patriots had 10 black starters on defense. I don't know why I'd never noticed before, but that was a real eye-opener. From then on, whenever I tuned in to an NFL game, I started counting their white starters on defense. Even at that point, no team in the NFL had a majority white defense, and most had only a few white starters.
I really think that linebacker was the crucial position in transforming the NFL from a league with lots of blacks into one with very few whites. Before the early 1970s, almost all NFL linebackers were white. That included the reserves, so just do the math on how that could have transformed the racial numbers. Coupled with the fact that most teams, at that time, began switching to the 3-4 defense, and you can just imagine the massive amounts of black players who entered the league during the 1970s, exclusively at the linebacker position. I recall the early Caste fervor that the jock-sniffing announcers had for the likes of Isiah Robertson, a linebacker the Rams drafted to take the place of dull, plodding whites like Jack Pardee and Maxie Baughn. The media wildly overrated these new black linebackers, and they certainly made the Pro Bowl in undeserved numbers. I can recall the lust the jock-sniffers had for Thomas "Hollywood" Henderson when he burst on the scene as a rookie with the Cowboys in 1975. They raved about his speed and "athleticism," and paid way too much attention to every play he made (and he didn't make that many). He was the first modern-style black LB, imho, which would culminate in Lawrence Taylor a few years later. The media reaction to this new wave of black linebackers was very similar to the love fest we see today towards black quarterbacks.