Similarity scores thru age 29: Jimmie Foxx Hank Aaron Lou Gehrig Ken Griffey Frank Robinson Mickey Mantle Juan Gonzalez Mel Ott (794) Hank Greenberg Orlando Cepeda That's 8 HoFers plus one to-be HoFer and one probably not (JuanGone) All were high average/high power guys who had great early careers and mostly played (exceptions Cepeda & Robinson) during good offensive eras - especially the 1930s crowd of Foxx, Ott, Gehrig & Greenberg. Of that group, Mantle, Griffey, Cepeda, Ott, and especially Foxx & Gonzalez, had considerably better years in their 20s than in their 30s. Only Aaron really got better (more power). Cepeda (the least similar to begin with) was the only borderline HoF vote. Gonzalez's fall-off (last full season came at age 31) was the only one that will likely keep him out. His overall similarity scores are also a bunch of players who either fell-off early (for various reasons) or, like Albert, are still works in progress. Hank Greenberg (WWII interrupted career) - HoF Albert Belle (career ending injury) Lance Berkman (still active) Johnny Mize (814) (HoF) David Ortiz (active) Dick Allen (grumped his way out of the game) Mo Vaughn (injuries, weight, steroids) Todd Helton (active) Ralph Kiner (cut short by injuries) - HoF Chuck Klein - HoF