Maybe...but what about the fact that Shisui uses KA in both eyes? I know this is off the original topic, but now I'm just curious. I mean, for Itachi, each eye has a different technique, with Susanoo being both eyes. But both of Shisui's eyes can use KA. What's the deal?no, i wont, ever.
its possible his other tech was too weak with him, like Sasuke and Tsukiyomi, to be used much or he didnt develop his MS enough to use the second tech. these two things plus the incredible ability of KA could have caused people to not care for his second tech