Nothing short of removing all devices identifiers (IMSI, IMEI, etc) and using an untraceable payment system for network access (eg blinded tokens) will mitigate the location tracking ability of the carriers.
The perfect is the enemy of the good and cops do use stingrays for a reason. But targeted government surveillance is only one privacy threat, and carriers have no compunctions about bulk selling your location to the mass surveillance industry.
Yes, and I did recognize I was talking about a different vulnerability by saying that the perfect is the enemy of the good. But if we're talking about protocol vulnerabilities, why skip over the deep flaw of having fixed identifiers in the first place?
Heck, simply removing the IMEI so that users don't have to buy a new burner phone (/mifi) along with every burner SIM would be a vast improvement!
Really I'm just pointing out the larger context, as it's important to keep in mind. Shoring this up will make the keystone cops have to go get a warrant, but won't help versus the NSA, parallel construction, or GoogleNexis. It probably won't even make private investigators have to eat lunch in their cars again.
The perfect is the enemy of the good and cops do use stingrays for a reason. But targeted government surveillance is only one privacy threat, and carriers have no compunctions about bulk selling your location to the mass surveillance industry.