The implementation appears to take a positioning element, (let's call it "pos"), and then start at an annotation where
* for following: the begin is > pos.end * for preceding: the end is < pos.begin The Annotation index guarantees that "begin" positions are in ascending order as you go thru the index. But there's no such guarantee for "end" positions. They can jump back and forth. So the logic for preceding: starting with some annotation whose end is < pos.begin in no way guarantees that all the found annotations will have this property. What was the design intent for preceding? If it was to get FSs that precede the pos in the index, then this logic is not doing that - it's initially skipping some number of preceding items (where the preceding FSs have ends >= pos.begin), and then providing results where the end could easily bounce around the pos.begin position. -Marshall
