Better? Yeah, that's not happening. When he's in the sensor mode, that's when he's focusing his chakra to sense things, he isn't in a position to fight. That's not the type of sensor skills that Muu and Tobirama has, he is far below them when it comes to that. Muu could battle and utilize his sensor skills at the same time
Attributing him noticing Obito behind him to his chakra sensing? Nonsense, you must be forgetting that ninjas have other tools to notice things , hearing, smell? Overall having a prescence
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Oh god, I guess Itachi really was a sensor, considering the amount of times he's noticed people out of his range of vision
And Ive said this already, his feat in sensing naruto wasn't a sensor skill, everyone, down to Orochimaru and Sasuke was sensing Naruto and Kyuubi's chakra..
Now back to the original point of his skill making no difference on how the fight will go. Especially considering he has no manga knowledge on Itachi and his abilities.
No, they are no better. Minato has better sensing feats. What you're talking about though is the difference between active and passive sensing ability. It's not what i judge to identify who is better sensor than who, and it's also not what you must use. The better sensor for me depends on what he is capable to sense when his sensing ability is active and in this case for the reasons i already listed, Minato's sensing feats are better.
To active your sensing now, you need to mold chakra. Besides Karin who uses the eye of Kagura, no sensors are always actively sensing chakra, Muu and Tobirama included. Like i've said it's a general rule
Sensors sense all the time as long as they kneed/concentrate chakra
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Now if they are too distracted, it can happen they fail to notice something they normally should have
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Reason why none of Hokages(sensors included) sensed a thing before Orochimaru told them about war:
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Tobirama for example failed to notice Orochimaru's body was filled with his brother's cells before sensing it better(when Hashirama who was considered weak in sensing managed to):
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Tobirama also didn't notice Sarutobi's approach when he came to help Naruto:
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So i don't know how you find Tobirama different
So really it doesn't depend on your level on sensing in this case but it depends on if the sensor in question is kneeding chakra to sense or not. Minato was capable to know Naruto managed to control Kyubi and that they were partner fighting together from a distance, just like he noticed it was extracted, so Minato is capable to notice chakra build up inside a body.
Sensing in Naruto is no particularly different than in DBZ. They sense all the time but there are times it happens that when they are too focused on something like in Minato's case, they fail to notice. Like Picollo failing to notice Cell's presence:
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Or Kurillin failing to notice Bejita behind him:
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As for your question concerning the purpose in this match-up i already replied in the thread. Tsukuyomi isn't landing when a sensor can sense the build up and avoid it before it even happens
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