ALAMEDA -- Beleaguered Raiders offensive coordinator Greg Knapp knew what was coming.Before even taking the podium following Thursday's practice, he turned to the assembled media and smiled a, well, a knowing smile."Lets keep things in perspective for a second here," Knapp said, before any questions were asked. "Weve played two games in the regular season on offense. Weve had two different centers and a right tackle who played half a game last week. We need some patience. You cant develop a scheme in two weeks in a regular season, especially when last week we faced the No. 3-ranked rush defense from 2011 and the week before they held the No. 2 rush offense in the league to 2.4 yards per carry, the Houston Texans."That was a good team we faced last week. The scheme will be fine. It just takes some time."And there it is. The Raiders are not sweating the offense's lackluster showing, especially the run game, in starting out 0-2 with the run game being basically nonexistent. At least, not publicly.Darren McFadden, who was the most explosive running back in the NFL last season before a Lisfranc injury ended his season seven games in, has been rendered a non-factor thus far, averaging 2.1 yards per carry in Knapp's new West Coast Offense that relies on a zone-blocking scheme.And now, here come the Pittsburgh Steelers and their tough defense.NFL CAPSULE: Raiders vs. SteelersDuring training camp, Knapp compared installing a new offense to a start-up company. So he's not really surprised by the lack of success running the ball so far. But not for the reasons you'd think. The gameplans for the first two games, Knapp said, called for the Raiders to throw the ball more than to run it."That wasour strategy going in and we had success doing it," he said. "Part of it is strategy and part of it is going to be a learning curve. We have to go through the experience of games against different defensive schemes that our guys will learn then changing the parts, the position of center is critical to what we do. He had a good learning experience last week."Thats the first time hes played, in defense of (Stefen Wisniewski). He played six snaps in the first preseason game and that was it. He jumped in there and did a very admirable job considering how little time hes had to play live."Of course, with the success the Raiders had last season in the power-blocking system, many wonder why the Raiders, under rookie coach Dennis Allen, had to change the offense at all.In fact, former offensive line coach Bob Wylie told SiriusXM Radio this week that McFadden was simply too fast to succeed in the more wait-and-see ZBS.RELATED: Gutierrez: Can McFadden thrive with zone-blocking scheme?"I have to speak to my experiences," Knapp said. "The guy who was in Houston (Arian Foster) was a pretty fast runner as well, and he fit in fine with the zone scheme. He also was a young back with an offensive line that had run the scheme for five years and he reaped the benefits of having a line that knew all the nuances."Justin Fargas, when we were here in '08, ran for 1,000 yards and he had a lot of speed, too. I feel very comfortable that the backs we haveDarren McFadden, I dont care what offense you put him in, hes going to be fine. Hes a good running back in all schemes. Well be fine."The issue, then, with the ZBS is that it takes an offensive line more time than usual to learn it and implement it, especially since the line cannot practice cut-blocking on its own team.So, how long does it take to implement this system?"A lot of it depends on who the parts are," Knapp said. "At four different places, Atlanta, here, Seattle and then when I was in Houston, it was already in play, there was a different running back, five different linemen and a different coach. And all places theyve had success where we did it at. It depends on that group of players. Were a little bit younger right now on the O-line than I have been at other places so it takes a little bit longer for them to learn the nuances. A lot of the experiences goes on Sundays."You think about it. We faced one defense the last six months, our own. Now were playing different schemes. So youre going to have some learning parts that go through game experience to help develop the offense."Then how close is it to working? And no, don't hold your breath, Raiders fans."It will take a little while, it will take a little while," Knapp said. "I dont know what the set time is. A lot of it will be changed week to week based on who were playing. Its making progress, its making progress. It may not look up statistically but in the execution on cut blocks, combination blocks, were seeing progress being made."