CC "Struts" may limit girth growth
This article says that “struts” help contain the diameter of the CCs during an erection. Therefore, the strength of these “struts” may be a limiting factor in increasing girth.
The tunica albuginea of the penis(above) consists of two fibro-elastic connective tissue layers, an inner circular and an outer longitudinal. The inner circular connective tissue layer serves to contain the erectile tissue’s diameter during erection. This is analogous to inserting a balloon into a drinking straw and attempting to blow it up. In the corpus cavernosum, this layer is also continuous with “intracavernosal struts” or spokes radiating from the connective tissue surrounding the cavernosal or deep artery. These act to increase the ability of the circular layer to contain the diameter of the expanding penis.