A question with a similar title has been asked before, but it doesn't answer my specific question here. PCI DSS permits storage of truncated and encrypted data, or hashed and encrypted data. It explicitly states that hashed and encrypted data should not be stored together due to the possibility of breaking the hash.
Truncated data is permitted to be first 6, last 4 of the 16 digit credit card number such that the middle 6 digits are masked.
If I were to store the first 6 and last 4 in clear text and encrypt the middle 6 only, is this less secure than storing the truncated data as well as the full encrypted PAN?