How do you account for slower and smaller defenses in that estimation?
Why assume that while everyone else was getting bigger, stronger and faster, the players we are talking about when hypothetically transporting them from one generation to the next would not also get bigger, stronger and faster? The same advances in training, nutrition, etc. would be available to the players from previous eras in this scenario. The expectation should be that those older era stars would still be bigger, stronger and faster than other players today.
Sure, Sanders and Smith are recent history, but the others go back to another era, which makes things harder to compare.
Since the way the game is played, coached and officiated is constantly changing, the best way to compare players from different time periods is not head to head, but instead compare them to their peers.
Case in point: at the time he retired, Vinny Testaverde ranked fifth in career passing yards. Was he the fifth best QB in NFL history? Today Eli Manning ranks eighth. Is he even the eighth best QB in the NFL today, never mind a top ten of all time? A quick look at how they compare(d) to their peers confirms that neither is a top ten QB of all time.
Also, Brown, Dorsett, and ****erson stand out as being much different in style. Long striders, thinner in the middle but sometimes with more inertia (mass), and generally less capable as receivers.
In the middle of his career Brown had back-to-back seasons totaling 93 receptions for 976 yards, and had more career touchdown receptions than one of the two running backs you listed as an all-time favorite (LaDainian Tomlinson). In Dorsett's first nine seasons he averaged 38 receptions per year. ****erson had 51 receptions as a rookie, and 41 in his ninth season at age 31.
Jim Brown led the league in rushing in eight of his nine seasons; by comparison Marshall Faulk never finished higher than fifth. If you want to include receiving, compare yards from scrimmage. Brown was 1st six times, 2nd twice, and never worse than 4th. Faulk had two 1sts, two 2nds, a 4th, an 8th and six seasons outside the top 10. Dorsett had nine seasons in the top ten. ****erson led the NFL in yards from scrimmage four times; Tomlinson did so only once.
Expand to all-purpose yards and the results are similar. Brown led the league five times and was 2nd twice. ****erson led the NFL three times and was in the top four five times. Dorsett was in the top ten six times, with his best years finishing 3rd and 4th. Tomlinson finished 2nd twice and was in the top ten six times. Faulk led the NFL once and was 2nd twice, but was in the top ten only five times.
Scratching the surface and looking beyond the gross career receiving stats reveals that the old timers were just as capable as receivers as Faulk and Tomlinson. Brown, ****erson and Dorsett's abilities should not be dismissed simply because in today's NFL more play calls are made for screen passes to a back.
For them, I say that they were great for their time, but they wouldn't have the same advantages in today's NFL.
Based on that thinking any 'greatest of all time' list will always be equal to the most recent all-pro team - which renders any 'best of all time' debate utterly useless - unless you also believe that tomorrow's players are suddenly going to stop receiving better training, nutrition, etc. and they will stop becoming bigger, stronger and faster.
