While not quite on the overrated bandwagon, this begs for some analysis.
You must be thinking of a different Herschel Walker.
He averaged 4.2 yards per carry, 9.5 yards per catch and averaged 9 TDs a season (excluding his USFL numbers).
OK, but now for a little context not given.
Walker - 1,954 attempts
Placed in historical context:
Barry Sanders: 5.0, 8.3, 11 per season - 3,062 attempts
Walter Payton: 4.4, 9.2, 10 per season - 3,808 attempts
Jim Brown: 5.2, 9.5, 14 per season - 2,359 attempts
Emmitt Smith: 4.2, 6.3, 12 per season - 4,409 attempts
Now let's think a second here.....what if Walker had had to carry the ball an additional 400 times? Emmitt Smith may have had the same ypg average, but he also carried it more than TWICE AS MANY times as Walker did, which means he got hit a LOT MORE AT AN OLDER AGE than Walker did. If Walker had additional carries, his ypg average would have dropped.
Furthermore, he was so "good" at 24 that he split the carries with over-the-hill 32-year old Tony Dorsett. In his last four seasons with Philly and the Cowboys, he was mostly a fullback or kick returner. I mean, if he couldn't play enough to even start when he was 34, why should I think he can play at 52?
Including USFL: 4.5, 9.9, 11 per season
Yes, let's count the statistics from the equivalent of AA ball with the major leagues. Most of the "NFL" players in the USFL were guys the NFL didn't want anymore (Cliff Stoudt, Brian Sipe) or who weren't any good. Yes, there were a few Hall of Famers, but that would be true of any league (Reggie White, Steve Young, Jim Kelly). Steve Young ought to be thanking his god every day of his life. What if he'd signed with the Bengals (who drafted him) instead of the LA Express?
If you included USFL in his totals, he'd be 5th all time in rushing yards and 2nd all time in rushing TDs.
Let's count Otto Graham's AAFC stats and Josh Gibson's Negro Leagues records, too.
You and I have different ideas of what under-achieving means.
Yeah "underachieving" is a little bit harsh in my view. But no more ridiculous than mentioning him in the same breath with Emmitt, Walter, and Barry Sanders (to say nothing of Jim Brown).
Walker should have been the first freshman to win the Heisman. That is TRUE. But he was a steady talent and not the breakway back we saw at UGA.
My bottom line point is that there is no way - no matter how great his body looks or MMA or whatever - that Herschel can play in the NFL today. There's a HUGE difference in a one-on-one fight with rules and getting hit by three guys whose combined age is not much older than Walker running full speed in pads is a completely different thing.
Not a chance.