I am glad for Ven. Dhammanando's opinion, above. It seems to me that a part of the cultivation of the lay Sangha would be having Bhikkhus/Bhikkhunis involved in important events in the lives of lay people. Certainly, monks are there for the questions and answers, pindabaht, Dhamma talks, the house blessings, are there for the funerals...so it would seem to be a good thing to have these monks as celebrants for one of the most positive events for many families. It would be a shame for a monk to turn down a couple that he/she had counseled and taught, based on a Vinaya interpretation that is subject to ambiguity or a more compassionate view. I wonder if the engaging Ajahn Brahm, who must get asked every week to celebrate a marriage from members of his Sangha, still holds to his early position as he stated in his brief.