Thomas Jones did next to nothing over the course of his career before last season. Forgive me if I'm a bit skeptical.

I count 2 solid years in Chicago, and on an offense that couldn't pass to save its life. 2004 Chicago Bears 14 games, 240 carries for 948 yards (4.0) & 7 TD's
2005 Chicago Bears 15 games, 314 carries for 1335 yards (4.3) & 9 TD's
Also consider LeMont Jordan's stats before he started in Oakland:
Year Team G GS No Yards Avg Lg TD 20+ 40+ FD
2001 New York Jets 16 0 39 292 7.5 46 1 3 14
2002 New York Jets 14 0 84 316 3.8 61 3 1 17
2003 New York Jets 16 0 46 190 4.1 39 4 2 14
2004 New York Jets 16 0 93 479 5.2 33 2 3 27
2005 Oakland Raiders 14 14 272 1025 3.8 26 9 4 61