Thanks for this & I hope it brings forth more substantial evidence.
As a non artillery specialist & without really thinking about it I had just thought it was just a matter of putting metal balls into a container & blasting it at the enemy. However some of the points raised suggest it was more complex & possibly artillerymen actually put more involved thought into the design of cannister & I found this possibilty interesting. Do you want to use it very short range when a wide dispersal is wanted very quickly or would it be beneficial to hold the balls together to perhaps give more range? Did different nations have different ideas on its use? As you quite rightly point out generalised statements will not apply to different types of munition.
By the way I didn't see your post as a rant I thought it a well reasoned argument.