Preparing to order my first MacBook Pro and have a simple question concerning Time Machine. Since TM will be backing up to an external hard drive it obviously needs to be connected to the hard drive to back up. Since I'll be using the MBP untethered it will not back up hourly. So, to back up with the machine do I then just have to connect it to the external drive and leave the MBP turned on. This would seem to me as the only way which really takes away from the hands off automatic nature of Time Machine. Just a note, I already have a top of the line ac router so I will not be using Time Capsule Extreme.