Can Alpert Time Travel?

There are theories out there that Alpert and his appearances in Locke's young life are attributable to time travel. His lack of aging plays into that theory. But here's what I can't understand. How does Alpert control his time travel? The only physical time travel that we know we've seen so far is Ben post-donkey wheel turning. And I think it was pretty clear that Ben didn't know where or when he was going when that happened.

Has Alpert perfected the pinhole opening we see in the latest Marvin Candle video? And if so, why aren't others (like Ben) using it on Island as well? Or are they?

So what do you think?