He's a RF, not a 2B. But yeah, maybe it is somehow tied to the league average range at each position. The top RF 'ers for "+" plays in this league are:
1985 Willie McGee (A range) 22
1905 Mike Donlin (B-) 21 (got one more in the PM game!)
1954 Mickey Mantle (B+) 13
1996 Albert Belle (C+) 12
1926 Freddy Leach (B) 11
My pitching staff was mostly modern guys, with fewer than 400 out of 1400 IP being deadball era, so I guess that helped Donlin too. Contrast that with 1985 McGee, in 1st place above, who's on an all-deadball pitching team.