[RobT]

Ian,

Save for the functional superiority issue, your conclusions and mine generally agree. I would have put the one piece version’s first appearance as in the last quarter of the 19th century if not later because five of my examples have a ganja iras and the other three have ganja fitted very closely to the blade (think crankshaft bearing tolerances). However, I’m not really sure whether these ganja iris and tightly fitted ganja first appeared in the mid or in the late 19th century.
I am not very good when it comes to using the Cato classification but, of the eight kris in my collection with a one piece baca baca, five appear to be Maguindanao, two appear to be Maranao, and one appears to be a crossover. One of the Maranao blades tapers distally in width from 2” (5.08 cm) at the baca baca to 1.5” (3.81 cm) at the last luk and has 19 luk in its 22.75” (57.785 cm) length. An odd looking blade for sure.
My reasons for thinking that the one piece baca baca was deliberately created as an improvement over the two piece version are as follows: I don’t think that there can be any question that, all other things being equal, the one piece design would provide greater torque resistance than a two piece version. A blow struck with a large and wide blade can be expected to generate more impact and torque forces than a blow struck with a smaller and narrower blade. As you noted, the one piece baca baca appears most often on large, wide blades and, in the examples I have, only the crossover is of average size. The other seven blades are large and wide. A closely fitted ganja (or better yet a ganja iras) would also have helped the kris hang together during the rigors of combat. I suspect that the one piece baca baca was more than just a style and the smiths were trying to sell the notion that a single one piece version could perform as well as a pair of the two piece kind but were perfectly willing to fit a pair of the two piece baca baca should the customer be unconvinced.

Sincerely,
RobT