The history of (future) Hall of Fame and Norris defensemen before age 22

Here's a chart of 99 defensemen, culled from one (or more) of three lists: (1) the highest-scoring defensemen all-time (500 career points or more); (2) the currently highest-paid defensemen in terms of cap-hit; (3) the top-scoring defensemen over the last couple of seasons. I thought I would show that Doughty, before the age of 22, has done what few before him have done. That was simple enough: Doughty has scored 126 points in those three seasons, a feat which has been topped by only thirteen other players.

• The "H" column has an asterisk in it if the player happens to be in the Hockey Hall of Fame.
• The "N" column gives the number of Norris trophies won. 
• Players whose names are in red are both Hall-of-Famers and Norris winners. 
• Players whose names are in orange are merely in the Hall of Fame. :(
• Players whose names are in green are Norris winners who aren't in the Hall, although some of them will certainly be in the Hall soon (Lidstrom, Chelios).
• Names in purple are either active players or recently retired (purple being the default color for links to an SBN player page). [oops, the SBN tagger is having technical difficulties; purple links aren't happening]
• The columns 18, 19, 20 and 21 reflect the number of points earned by that player at that age. 18-21 indicates the total for that period. R1 shows the rank at 18-21. RC shows the rank of the player's career totals with respect to the other players on this list.

• There is an obvious divide in the list: Niedermayer and up representing the franchise-type players; Hatcher and down representing the very good but not elite. This, of course, begs the original question, or I guess rephrases it:
• Is Drew Doughty closer to Bourque, Murphy, Potvin and Leetch...or Hamrlik, Reinhart, Wesley and Bodger?
• I decided to look at the next block of four years, ages 22-25, to see if it was a better predictor of career numbers. Obviously, Doughty (and many others out of the 99 we started with) don't have data here because they're not 22 yet (or are, just barely). I have once again focused only on retired (or nearly retired) players.

• The thing that leaps out at me is that looking at the numbers for defensemen at this age is a much better predictor of career numbers than looking at numbers at age 18-21. 
• R22-25 is the player's rank (out of the 99 players I selected) in terms of their total points between ages 22 and 25. RC is their career rank, among the same 99 players. If you compare the top 15 in both lists: (22-25) the nine players whose rank fell in terms of career totals averaged a drop of 7 spots; (18-21) the nine players whose rank fell in terms of career totals dropped an average of 20 spots. 
• Over-all, the 22-25 top 15 dropped an average of 3.6 spots, while the 18-21 top 15 dropped an average of 11.4 spots. 
• Interestingly, 7:20 reduces to 1:2.86 and 3.6:11.4 reduces to 1:3.16...both very close to 1:3.
• In other words, a randomly selected player in the top 15 in the 18-21 column is likely to fall nearly three times are far down the career list than a randomly selected player in the top 15 at 22-25. 
• And if Doughty were in the top 15 of the 22-25 group in four years, instead of worrying he's going to turn into Hamrlik, Reinhart, Wesley or Bodger, we would be worrying he was going to turn into Steve Duchesne or Reed Larson. 
• So, from the 22-25 list, not only are there fewer bad outcomes, but the bad outcomes themselves are upgrades over the bad outcomes of the previous list.
• Which tells me that, while what Doughty has accomplished so far is certainly something special, something only 13 players in the history of the league have managed to do, it's not a reliable predictor of future eliteness, greatness, Hall-of-Fameness or whatever other attribute one might expect in return or $7MM a year.
• That would be an easier argument to make if Anze Kopitar weren't getting $6.8MM, arguably having accomplished less.