(a) A shareholders' agreement executed in accordance with Section 21.715 is valid and enforceable notwithstanding:
(1) the elimination of a board of directors;
(2) any restriction imposed on the discretion or powers of the board of directors or other person empowered to manage the close corporation; and
(3) that the effect of the shareholders' agreement is to treat the business and affairs of the close corporation as if the close corporation were a partnership or in a manner that would otherwise be appropriate only among partners.
(b) A close corporation, a shareholder of the close corporation, or a party to a shareholders' agreement may initiate a proceeding to enforce the shareholders' agreement in accordance with Section 21.756.