Otherwise, Master Gigo Funakoshi at least knew what could be one of the two Sakugawa no kon, seen in a few pictures of his bojutsu form. I am uncertain as to whether it could be Matsukaze no kon, the bo kata created by Masters Gigo and Okano. It looks more like one of the classical exercises. Whether or not he learnt it from his father is unknown, if it is one of the old forms. It would certainly be logical that Sakugawa no kon was a kata which Master Gichin Funakoshi knew. But there is logic and then there are facts. Mr Bob McMahon also mentioned in the forum feed about Master Gigo Funakoshi knowing Shushi (Shuji) no kon additionally. In Keio University karate the students practise Sakugawa no kon and Shushi no kon, so this possibility is interesting as well as plausible.
Now, Master Gichin Funakoshi had a chance encounter with Master Sueyoshi, the bojutsu expert who devised Sueyoshi no kon. Master Funakoshi explains that they ended up discussing karate and the art of stick fighting, but he did not state anything about having learnt Sueyoshi no kon (comprising Shuji no kon and Choun no kon, not a kata called Sueyoshi no kon or Soeishi no kon) as a result, sooner or later. Perhaps he did, but reading that he did learn the kata is not valid, since there is no actual evidence to suggest that he was taught by Master Sueyoshi. Surely he would have thought to record such a fact while he was noting their "meeting", and as he mentioned Master Sueyoshi founding his own school of bojutsu.
There is a DVD that presents footage of the sensei of Keio University karate demonstrating some kobujutsu kata within their lineage of Shotokan karate. It is Keio-ha Shotokan karate, I suppose, because it includes other kata outside of the "standard" Shotokan "syllabus", such as suparinpei. The kata displayed are Sakugawa no kon, Shushi no kon, and [what you could call] heian / pin'an [shodan / nidan] no sai ("sai no kata"), as well as pairwork with these weapons. When stating the history of their kobujutsu, the teachers are unsure of details, so cannot say for certain that Master Gichin Funakoshi was the one who taught these kata to the students of Keio University. Though, knowing that Master Gigo did practise at least [what looks like] Sakugawa no kon, there appears to be some direct link to seito Funakoshi karate.
Saijutsu kata is another story. I don't personally agree with the way the sai is applied in heian [shodan] (pin'an [nidan]). It is not realistic. Perhaps Master Gichin Funakoshi did not practise any sai kata, and only studied pairwork using sai against a bo, as photos illustrate. He did study under Master Aragaki (Niigaki), who was a noted kobujutsu expert and who even devised his own weapons kata such as Aragaki no sai. Master Funakoshi learnt Aragaki's unarmed kata niseshi and unsu (probably sochin, too, though he did not perpetuate Aragaki sochin in his kenpo). Therefore, he may well have been taught kobujutsu by Master Aragaki, additionally. But, again, this is not known fact.
From years ago, I decided to apply the karate kata that definitely fully suited certain weapons / tools, so as to practise the kobujutsu most evident in Funakoshi karate, even if the original intent was actually just for partial weapons use by defending from beginning empty-handed, but then to just apply other techniques completely unarmed. It may not be known with absolute certainty, but there are various sources I have noted that inspired me to go about studying particular karate kata with certain implements. While you can (and perhaps should) apply any karate kenpo kata to kobudo with one or more weapons, they do not all fit perfectly. Those that indicate, for example, some use of the staff, offer definite clues, while others show positions that compare with "actual" kobujutsu kata of the sai and kama, for instance. However, niseshi, for example, is noted to be a saijutsu kata. It works well as such, but I wouldn't say significantly so.
However, if kata other than Tenryu no kon should be avoided in the absence of solid evidence, the kobujutsu of Master Funakoshi's Ryukyu kenpo is mostly simply kumibo and kumisai, following the teachings presented by Master Gichin Funakoshi himself. Yet, that doesn’t mean that other teachings can’t be added by anyone. Gichin Funakoshi himself sent Gigo Funakoshi and Masatoshi Nakayama, for instance, to learn from others such as experts in Okinawa, and Master Kenwa Mabuni, respectively. Karate must be allowed and encouraged to continue to grow.
S. R. Marshall