I do not know anything about Moro weaponry, but I do have considerable background in Javanese and Balinese weaponry.
In these cultures a spear intended to be used in the hand and not thrown usually has a much more substantial shaft than this one, a shaft that swells in the mid point to afford better grip.
I agree that the quality of the blade of this spear could indicate a weapon used on ceremonial occasions, however the narrow section shaft seems more to indicate a thrown weapon.
The Roman pilum was a heavy thrown spear that weighed up to 8.5 pounds, and could travel 90 feet or so.
Cord spear throwers are well known and widely spread. Use of cord spear throwers is recorded in the Pacific region.
http://www.nma.gov.au/cook/artefact.php?id=337
http://www.geocities.com/Colosseum/8682/jav.htm
http://dictionary.reference.com/brow...20thrower?r=14
http://en.wikipedia.org/wiki/Pilum