Yes; probably not.
http://ojs.sagepub.com/content/3/4/2325967115581594.full
The timing of the arm and body is important, but it's not as simple as looking for the inverted W. What "early trunk rotation" means, essentially, is that the shoulders are turning before the arm is 'cocked'. Imagine the whole body firing to deliver a pitch, but the arm is a bit late, so it drags behind. This increases stress on the arm (and also, probably, velocity).
There are physical things you can look for up and down the body to get a sense of timing. Look for where the arm is at foot plant. Look for where the arm is when the front shoulder is in the process of turning. Look at whether or not the hips turn before the shoulders. Look at how stiff the plant leg is through the pitching motion. Look at the path of the arm after releasing the ball. All of these things can influence injury risk - but the inverted W probably doesn't on it's own.
Note that the study linked may not be perfect. At a glance, there might be sample size concerns.