Kakushidi wrote 'No military leader would ever choose Okinawan implements for use in warfare, when long bladed weapons are what are needed to be successful'.
Reality is that many of these implements were not household implements as you state, that is a bit of a myth created around another myth of the weapons ban and the emergence of agricultural and household implements. The Rokushakubo is seen in Chinese as well as Japanese military traditions, in fact some techniques in some traditions are or may be the same as spear.
As to the issue of Okinawan Karate and martial arts generally being battlefield arts, this is extremely unlikely, it is a civilian fighting tradition, perhaps with soem extention to bodyguarding nobles, so again still civilian tradition.
The argument that Kata movements were tested on the battlefield I am afraid is to my mind at least absurd. As cxt correctly states the Okinawan traditions for self protection were based on Chinese systems of self protection. There appears little evidence to support what it is that you arguing, or at least you have not presented any.
Kakushidi wrote 'It is my belief that each kata was likely a full-blown battlefield art'.
I doubt that was the case, Sanchin most certainly was not and I have my doubts about Naihanchi as well. Some of the Kata can be traced to tehir Chinese origins and there is no suggestion of what you are proposing here. What is more intringuing is that you seem on your website to link spear to a Pinan Kata, Pinan's were created by Itosu for the schools system in Okinawa.
I do not doubt that there were spears on Okinawa and that these were used in a martial sense at some point, but have you looked at dance drama's of Okinawa?
There is a picture in Mark Bishop's (2009) Okinawan weaponry: Hidden Methods, Ancinet Myths of Kobudo and Te. Way Publications on page 91 of a picture from the 1900's showing some children preparing to do a dance with Yari or spear.
Have you looked to Matayoshi Kobudo were they use Tinbe and Rochin?
Have you considered traditions in Okinawa that still use the spear, the Motobu ryu Udun Ti and the Bugeikan?
Chris Norman LL.B (Hons) MA (SOAS, London)