Only if you don't use a TPM PIN and/or have a <2.0 TPM. Bitlocker using TPM with PIN has no way to know your hard drive key without asking the TPM, which requi

Only if you don't use a TPM PIN and/or have a <2.0 TPM. Bitlocker using TPM with PIN has no way to know your hard drive key without asking the TPM, which requires the PIN (and has anti-hammering/lockout built in.)