At least with Parssinen I think the rationale with moving him to wing was ok and it was the execution that was the problem. We had two center spots and three potential centers (Novak, Glass, and Parssinen) so something had to give. Brunette chose to move Parssinen and gave him the offseason to get acclimated there. I think the mistake was once things weren't working out with Parssinen at wing and Glass struggled at center he then wouldn't commit to what he wanted to do with Parsinnen. That resulted in Parssinen bouncing around the lineup and between playing center and wing, which isn't a great environment to put a young player in.
As far as Glass now it seems like moving him to wing would be a desperation move in hopes that since wing is "easier" that maybe he can get going there rather than any sort of calculated plan. However, while I do think it is easier for a center to switch to wing than a wing to switch to center I don't think that means that any the center will do better at wing. For example, while there is less defensive responsibility on the wing things like making breakout plays on the half wall aren't easy plays especially if you haven't practiced doing that for several years as is the case for Glass.