Sure. As a DM designing your own adventures you're not bound by what's in published modules. My point is that, while the developers say they expect a 2/3 - 1/3 noncombat to combat split, I don't see that reflected in what has been designed for the system. The DMG, for one, doesn't have any guidance or advice for creating noncombat encounters in its Creating Encounters section -- there's some explanation of why encounters should happen, but otherwise it's all about combat.