Vincent, thank you for this feedback. So, three types of bamboo, Moso, Henon, and Guadua, all requirering a certain "treatment" I assume to the outside skin of the bamboo. Do you know if that would be an oil, or some kind of sealer, like an epoxy sealer?
Also, I think I read in Practical Junk Rigs or Derek Van Loan's book, Design and Build your own Junk Rig, that two length of bamboo set head to foot and bound together throughout their length makes for one batten. My sail has pockets sewn into the sail, so the suggestion is then to slip the two pieces of bound bamboo into the sail pocket and then add a split third piece of bamboo on the apposite outside to bind the inside bamboo, to sail and outer bamboo together as one. My, my, I'm going bonkers! Somehow though, it seems a better settlement in terms of cost and repair ability. Break a stick of Ash or Fir and you might end up with wood for the stove.
Vincent, again thank you for your thoughts and any others you may have. I'll see what the growers of bamboo have to say and pass along whatever I learn.
With kind regards, Richard