Intake and Tuning Info

So I was at the Chevy dealer yesterday picking my buddies truck up. I decided to talk to my service advisor to find out the answer to whether you need to tune after an intake system. I was advised that if you use an oiled intake system that will consuse the MAF causing the vehicle to run lean. He said if you go with an oilless system and place a filter cover over the filter, like you would on a sandrail, then there is not any tuning necessary. Just thought I would fill you guys in... Getting an Oilless K&N Aircharger system tomorrow. I will let you guys know how it goes!