| | Re: 2 questions
1) I saw. The programme is a past event, so you need the past verb form. There's no suggestion of a connection with present time.
2) "that" in this sentence has the same meaning as "so". The sentence means I don't know how you move it so fast. Another example :
A : Put a coat on if you're going out. And you'll need a hat and gloves too.
B : Don't exaggerate. It's not that cold.