Understood, however to deny the fact there has been division within the Christian faith is just being naive (no offense).
I mean during the Nicean convention you had groups who believed Jesus to be God, Jesus to be simply a messenger/prophet, Jesus to be divine yet seperate from God. In today's society you have Unitiarians, Trinitarians etc. Church's that teach different doctrines in terms of salvation and about carrying one's self. This is severe division, especially considering all these different groups (although they might be cordial to each other) bear the Christian name.
The differing docrtines of belief is the point. I'm not alluding to the idea that the differing groups of Christians are at war with each, I'm simply stating that there are some pretty glaring differences between them in terms of doctines. If they were all unified in their teachings and doctrines then there would have been no division at all, hence the use of the term splintered.
This division is the very reason the restoration was needed and the very purpose for which Joseph Smith was called.