the omitted verb 'be'

I have recently read "A Piece of My Mind", and in the book, a story say about a married couple who agree to donate their brain-dead son's organs and therefore, receive so many letters of encouragement... ,
and in the story, the husband say afterwards "All this for a decision that seemed so obvious we've forgotten which of us suggested it."

In the sentence in bold, is the word 'was' omitted after the underlined phrase 'All this'?

In addition, in the spoken English there being a subject, is the verb 'be' often omitted?