Major Description
Currently the SegmentNodeState class simply inherits the generic compareAgainstBaseState() implementation from the AbstractNodeState base class. While functionally complete, this generic implementation is pretty slow as it can't leverage lower level information about how nodes are actually stored.
I already improved the situation somewhat by implementing a basic optimization in SegmentNodeState.equals(), but to get the full benefits of the segment model we should implement the full compareAgainstBaseState() mechanism based directly on the in-segment data structures.