The strongest way to secure a bitcoin wallet consists of create it offline and keep it offline.

As far my understanding goes, there is no way to check the balance a wallet without retrieving the transaction history. Hence, it should be possible to retrieve all transactions on an unsecure networked machine, and then to copy the transactions to a portable drive, and then re-run the Bitcoin client on a secure strictly offline machine to assess a somewhat not-too-old balance value for wallet.

Is my understanding correct? Is there smarter ways to achieve the same result?