Last two sets were basically him playing to full potential, and if he does that in the next match he'll get through Ferrer no problem.
Yes. The "If" is key though.
Murray seems not to have access to that level except at random. He was unbelievably useless in the first set today, then gets on top, but immediately donates the break back.
Do that against Ferrer and he'd have lost the match before he found top gear.