So, if someone has your phone, they have your phone's private RSA key. Jesus.
If memory serves, I sent Bruce Schneier an email about it and he replied with:
"Very interesting. Thanks."
Now that I'm older I realize the hard part would be keeping it secret that you're doing this, not actually pulling it off.
What's the point of buying into this model where a possessor (ie owner) of a device is considered an attacker? It hasn't even shown itself to be workable on general-purpose computers, meanwhile users' practical experience seems to be centered around companies that are attempting to hinder people attempting to retain ownership of their phone.
Especially as the main push is aimed smaller devices - exactly the ones easier to take with you! At a certain point, the threat from the past (undetectable tampered software) outweighs the threat from the present (due to being able to easily read out the entire device state). It's a bit tough to take a rackmount server into the shower with you, but there's very little reason for a usb-port-sized device to stymie the user for the goal of protecting against physical access.
Not really. Apple's Secure Enclave is resistant against many side channel attacks, including differential power attacks.
I'm just saying for most all of computing history (besides a few perverted niches), we've thought of the data on the device is accessible by the person who has the device. So this attack just puts us back at the traditional expectation - a place that a large amount of people would actually just prefer to stay.