(a) A debtor or secondary obligor may waive the right to notification of disposition of collateral under section 9-611 of this title only by an agreement to that effect entered into and authenticated after default.(b) A debtor may waive the right to require disposition of collateral under subsection 9-620(e) of this title only by an agreement to that effect entered into and authenticated after default.(c) Except in a consumer goods transaction, a debtor or secondary obligor may waive the right to redeem collateral under section 9-623 of this title only by an agreement to that effect entered into and authenticated after default.Added 1999, No. 106 (Adj. Sess.), § 2, eff. 7/1/2001.