Yeah didn't Signal spend a bit of work trying to avoid exposing users? If you have an existing Telegram device (registered before target registered), then how

Yeah didn't Signal spend a bit of work trying to avoid exposing users? If you have an existing Telegram device (registered before target registered), then how do they register? And wouldn't both devices get notified? Also how would they know which numbers to register? Just fundamentally seems like the software can notify you of how many devices have access, and make that visible on any change and when installing on a device. Perhaps even offering to kill existing devices.