Thanks
There are things you're misjudging concerning Gaaras defense. His normal defense(the sand surrounding him) is strong but not as strong his ultimate defense. His ultimate defense is when he uses all his sand to protect himself and form a coffin, what Sasuke explains here:
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So unless Gaaras uses all his sand to protect himself, his defense is not that difficult to go through. Now even when he did used that ultimate defense, Sasukes Chidori was able to go through it and even wounded him. So if Sasukes chidori was able to destroy
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and
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, Kakashis Raikiri will simply demolish him. Don't really understand then what you mean by difference in shape. Examples i gave must have helped you to understand that it's not Gaaras defense that will be enough to stop his Raikiri. He doesn't only even have Raikiri, he also has shown Raiden, what you didn't even mentioned in your post. What stops Gaara to cut through his sand with raiden? He also has Raikiri-kunai and other variants
Now you talk about crushing him while his hand is inside the coffin? Just to make you remember, Gaara uses all his sand to create that coffin. Which means inside the coffin he doesn't have sand anymore. What caught Sasuke in your picture wasn't Gaaras sand, but
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. Gaara partially transformed himself into Shukaku and it's his sand that wounded Sasuke. Furthermore, Kakashi was there to look at the scene don't forget that. So i don't think he will do the same error. He will simply go through directly and finish him. Even if somehow his hand couldn't go further, he can simply remove his hand after that. He doesn't need to stay there for hours. His job is already done. Gaara is at least wounded if not dead
Can you please shown me the difference between their defense? Again here you are misjudging. Since part1, his defense remained the same. The only thing that changed is the amount of sand Gaara can control and maybe the speed also, but his way to defend himself has always been the same. Against Deidara for example, again he used the coffin, simply because it is his strongest defense.
Even if i were to take a current example, i can talk you about Mizukages clone who was also able to go through Gaaras sand without problems
I didn't explained this part very well. What i meant is that, his sand is faster than the sand he can have in the environment like Deidara noticed:
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So if he gets far, he has less chances to catch someone with his own sand, which is the fastest sand he can use. It's the reason why when Gaara fights someone he always want to be near him to use his strongest sand to catch him. Even against Deidara, it's what he did. He used his sand to catch him in the air instead of controlling his sand by far distance. Why do you think he did that? Simply to increase his chances to catch him, to increase chances to catch his ennemy with the fastest sand he can use.
Talking about what he can use coming from the environment. I would say it depends where the fight takes place. Notice for example that in almost all the fight we have seen Gaara in, it's in a desert(against Deidara, desert, Mizukage or Madara, desert). Like Gaara said he can manipulate everything if there is sand. So it's normal that in a desert, he can use sand coming from a desert. But what if they were fighting in a place where there is no sand at all? And even when there is sand, like i've said, his own sand is faster, so better to be used. That's why Gaara is limited
Not really. In the contrary, this pic shows Gaara using his own sand. The original pic is this one:
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Look carefully where Gaara is. He is the one flying on the recht side. Look where the sand come from. It comes from his gourd like i'm saying
Like i've said. I didn't explained very well. I wasn't saying he can't control sand other than his own, but that his own sand is faster. What he did on your pic can only be done in places where there are a great quantity of sand(in desert for example)
Sorry but Itachi(smarter than Gaara) didn't knew, so i don't know why Gaara will know. The sand sensing comes from his own sand that he is able to manipulate
I don't know about Susanoo, but what i say comes from the databook:
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