I get sooooo tired of Windows either remember old stuff or forgetting new stuff. It is such a kludge of an OS.
For example, some devices that I have pair only to a single peer, while others have no problems switching between several, while another device is limited to two peers--requiring a reset if you want a third.
I suggest that anyone buying a bluetooth device test out pairing between multiple devices and if the device makes you jump through hopes to switch between bluetooth peers then immediately return it.
Too bad this method can’t be more generally used.
I'm surprised they didn't use some custom protocol, especially given how bad Bluetooth is, and they control the entire software and hardware stack.
edit: nevermind, just noticed you said magic trackpad 2
It's a huge mess and its not just a matter of the technology not working as designed. These are fundamental problems that nobody seems to worry too much about, apart from a small number of vendors (Apple did a decent job solving the pairing problem with the Apple TV: http://9to5mac.com/2013/07/29/new-apple-tv-os-offers-nfc-lik...).
I realise it's pretty hard to beat the intuitive action of plugging physical cables into devices to connect two things, but if we really want to get rid of cables, things need to be easier.