This property controls how the "common ancestor" is calculated when performing an RTC-SCM 3-way file merge.
By default (when this property is "false"), the common ancestor with the fewest number of versions between it and the two contributor versions being merged is selected.  When this property is set to true, the "lowest" common ancestor is used, which means the common ancestor that was most recently created.   For a discussion on this topic, and a simple example of when the lowest common ancestor is not the common ancestor with the fewest number of separating versions, see SCM does not use lowest common ancestor for a merge (287573) .