I am pretty new to cryptography and more of an economics minded bitcoiner. it seems like this is a non issue as far as security goes (because smarter people than me have not raised the issue) but I am still having a hard time wrapping my mind around how you can buy a new Trezor and recover your old wallets with the root code. I'm just not sure I understand that mechanism that remembers your old wallets without it being stored somewhere else
Everything is in the blockchain and the key is with U. To unlock something in the blockchain and use that, u need to employ your key. As long as U hold the key of your old wallet (and no one else knows about it), U control the sum. Its upto u whether U'll put it on Trezor, a paper wallet, Bitcoin-QT or a web wallet.