> (In reply to coldwill)
> You can see Stefano demonstrating this with a (prototype) Alpine Up in this video
No. The Alpine Up has an additional hole that allows it to be used as a guide plate, and that is what is demonstrated in the video. The Click Up does not have such a hole and can't be used that way.
You could use either device in its ordinary locking capacity on the anchor for an upper belay, but you can only activate locking by having the brake strand higher than the device, an unnatural position which, as AJ says, might require extending the anchor to lower the device.
Since the device used this way will not lock unless the belayer pulls the brake strand above the device, there is nothing automatic about locking at all, and unless the device has been positioned low enough that the brake strand is always above it during taking in, there is a definite risk of dropping the second.
The Click Up is basically a one-pitch sport and gym belay device. Get the Alpine Up if you intend to climb and perhaps rap off multipitch routes, but then fat single ropes won't work well or at all.