Split cane flight arrows are not my invention. I have learned they built by the Turks going back to their earliest days of formal flight archery. I feel that the only reason the Turks stopped making split cane flight arrows is that they didn't have reliable access to the best bamboo species, and found ways to make equally good wood arrows.
The restriction on forgewood has been dropped from the rules. For one, it is simply heated and compressed wood, and secondly, I feel forgewood is comparable to the more dense tropical species for a flight arrow material. The forgewood used in flight arrows I have seen is more of a liability due to its high density. They are either too heavy, or need to be so thin that they are not stiff enough. The restriction was originally put in place because there was a mistaken belief that the arrows were infused with some kind of synthetic resin. A second reason given is that forgewood shafts were no longer made and available to most people, but this point is only relevant if a forgewood arrow offers a clear advantage. Super short forgewood arrows were used with modern flight bows until carbon became available, but it should be noted that the farthest shots ever made using natural material shafts was done with Douglas Fir arrows made by Lee Sublette (1975, 1000+ yards).
I agree there is some good logic of disallowing sophisticated composite arrows with self bows. I'd be willing to put it up to a vote with the flight committee.
I wouldn't want to disallow the option of using composite arrows for the composite type bows however. Despite the lengthy process, a composite arrow of natural materials does follow the spirit of flight archer, going back to its roots.
The one beautiful fact about the existing primitive flight rules is how it limits the materials, but not design. This puts us on equal footing with those building flight equipment at any time in the past or future. I'd be reluctant to vote to allow synthetic string materials for a primitive record because it represents a major departure from this philosophy.
Alan