Not saying it doesn't happen, just saying I don't agree that in this case, that is the reason. Welbeck has a diverse skill set. Given the current state of our wingers, I feel he does a sufficient job on occasions (relative to who we currently have there, not relative to what we should have there). This means he plays there sometimes. The reason he doesn't play more as a striker is because, as you said, we have an array of players already at striker.
As I said, different ways of looking at the same story. You're saying he's been moved because of his skillset (which I disagree with). I'm saying he has been moved there as a) we have better striking options right now, and b) he has adequate ability to play out wide.
I disagree with you because I believe his best position is still striker. He has proved he can play there when he has been given the chance to.