That's your opinion though, others clearly have a different point of view. There are many things lacking "in depth" explanations, yet are enjoyable in the manga — An known, unknown you can say is what's interesting about such tools. Alas, we can't blame Itachi for his OP capabilities, as I stated before; Kishimoto has given Itachi, the keys to success.
There may be other things in the manga that lack explanation, not that I can even recall any, but no where near to the insane degree as Itachi's abilities. And I was never blaming Itachi for anything, he isn't real. For me, the lack of proper explanations about such seemingly over the top abilities is nothing short of another one of Kishimoto's many notorious examples of his train-wreck-like writing style and absolutely kills an legitimate care I could have towards Itachi. It's like if a character showed up in Naruto who was at some Goku-level strength and ended up dying by some dumb plot device (much like Itachi). I don't care how strong or flashy his moves are; they don't fit into the established world of Naruto nor are they explained, so they are nonsense to me.
When I first became a Naruto fan, I was still a kid, and Itachi was my favorite character because of all the typical things; edgy, calm, menacing, and super powerful, never losing any fights and always overwhelming his opponents in a calm manner. But nowadays, I don't care for such meaningless things, as, I said, powerful characters are NOT hard to create and not impressive, it's how they're written that I care for. Just like how Light Yagami, a normal human, will always be a well written character in comparison to Itachi despite a lack of any real powers.
