I apologize for my ignorance, but Trueview ads are the advertisements in which start on the actual video screen before the video even begins, and usually you can skip them after a period of time?
If that's what you are referring to, I think it's only plausible to say YES, it will decrease your view count. I'd put it on the lines of another example, Adfly. Obviously your click count would drop if you made your users wait 5 seconds, then click the continue button - I'm sure it would be hand in hand with Trueview ads.