While its ambitions seem grand, when you break the film into pieces, it's really just Jackie--by herself--which may be art imitating life.
More than anything, this film just feels like a jumbled mess. The film had four editors, and it shows. The only thing that would have been more obvious is if the film had also had four screenwriters and four directors, but the deficiencies in each of those areas are solely due to Mr. Beatty.
To say this film is a masterpiece would be an understatement. Masterpieces are the result of all involved being at their very best. With every crisp shot, immaculately delivered line and emotive thread in the breathtaking tapestry, that the people involved are at their very best quickly becomes a foregone conclusion.