Chris Johnson: 15-20 carries a game?

Due to his versatility, the expectations surrounding explosive rookie RB Chris Johnson have been centered upon his potential role as a dynamic jack-of-all trades back in the Titans’ offense.
Weeks ago, on this site, it was speculated that Chris Johnson’s ability to run in between the tackles and the potential for him to carry a little more weight without sacrificing his elite speed could lead to CJ becoming a primary back down the road.
If it’s up to Mike Heimerdinger, Johnson’s transition into being a main back could begin as soon as 2008.

In a radio interview conducted by Titans Radio, around the 9 minute mark, Dinger expresses his desire for Johnson to carry the ball 15-20 times per game. Despite Chris’s ability to catch the football and contribute on returns, Dinger’s hopes are geared around CJ making an immediate contribution in the running game.
Dinger compares Johnson to current Washington Redskins running back Clinton Portis, saying that CJ is around the same size as Portis when he entered the league. Portis averaged about 17 carries per game in his rookie debut in 2002, running for 1,508 yards while scoring 15 touchdowns on 273 rushing attempts.
It will be interesting to see what Dinger’s desire for Johnson to carry the ball 15-20 times a game will mean for incumbent LenDale White.
Last season, the Titans carried the ball 543 times while averaging roughly 34 carries per game. If the Titans run as much as they did last year, you’re probably looking at Johnson and White sharing the workload.
So what do you guys think? Should Johnson’s touches come in the running, receiving and return game or as Dinger suggests, should he primarily serve as a tailback next year?