(1) Article VII shall be construed and applied to promote its underlying purposes and policies.

  (2) The following are the underlying purposes and policies of article VII:

  (a) To make more comprehensive and to clarify the law governing trusts in this state.

  (b) To permit the continued expansion and development of trust practices through custom, usage, and agreement of the parties.

  (c) To foster certainty in the law so that settlors of trusts will have confidence that their instructions will be carried out as expressed in the terms of the trust.