much had been going on in the Fab 4 camp as far back as the mid-sixties, the band had created their own monster and it was inevitable they would go their separate ways.
Famous rock stars often say being in a band was like a marriage, and splitting up was like a divorce - driven by creativity they need changes to progress, such a creative force remained very prolific right up until the end, but the "Let It Be" movie was a shock for many fans who had no previous insight into the workings of a top band that had been together for years.
To answer the question Yoko was a catalyst but not to blame directly for the band's demise - in hindsight John Paul George and Ringo had run their course as a group in 1970, though in later years still worked happily together with each other occasionally without the pressure of being Beatles.
Edited by mystic fred - June 25 2009 at 11:12