(3) The nature and extent of other investments and resources, whether held in trust or otherwise, available to the beneficiaries as they existed at the time of the decision; provided however, that the fiduciary shall have no duty to inquire as to the nature and extent of any such other investments and resources not held by the fiduciary, held by the fiduciary in a trust or trust account subject to the direction of an adviser or cotrustee authorized to direct the fiduciary with respect to investment decisions, within the meaning of § 3313(d) of this title, concerning the assets held in the trust or trust account, or held by the fiduciary in a trust or trust account where a cotrustee has exclusive authority with respect to investment decisions, within the meaning of § 3313(d) of this title, concerning the assets held in the trust or trust account.
Any determination of liability for investment performance shall consider the performance of the entire portfolio and such other factors as the fiduciary considered when the investment decision was made.