@Chatte one perfume is stronger than the other because it's more concentrated. Yeah, that's exactly what happens in the manga. Some people have more chakra stuffed in them than others = Uchihas, Senjus, Uzumakis, Hyugas, etc. Which allows them to use Kekke Genkai.
The "chakra" itself, as a unit, is the same. Just some have more of it than others. Exactly the same principle as money, or energy, or anything else that stacks up.
Most basic concepts of this world. You don't need to be a rocket scientist to understand this.
Now then, I don't have to repeat myself any further from here on. My explanations on this are already documented well enough in this thread. If you still have questions, go back and read. Have a nice day.
Well, it can be more concentrated, but the amount be less than the other. So see, there you have your analogy failing.
More chakra stuffed into them is not going to make it more powerful and kekke genkai has nothing to do with chakra, since is a blood limit.
Another analogy since we're talking analogies here. Concentrated juice. A drop of concentrated juice is powerful enough, however, it's still less than when you add some mineral water or whatever you want in it.
It's the same juice, however, quantity speaking, it's different. Quality speaking, different as well. One is more sweet while the other is less since you already added some extra stuff into it.
Same here. In terms of chakra, for example, Sasuke's chakra is stronger given his heritage but unlike Naruto, he doesn't have that much.
And you know from where you can get it simple as that? [Generally speaking, not just to you].
By the simple basis of SHARINGAN GENJUTSU. Why is it that the Sharingan Genjutsu is one of the most powerful genjutsus in NV history? Because of the powerful chakra of the Uchihas, not the quantity.
Compare it to a genjutsu casted by Kurenai [who's said to be an expert] it's still superior. And not because Itachi had more chakra, but because his chakra was more powerful than Kurenai's. And they have both 5 in Genjutsu, but Kurenai isn't part of Uchiha clan. Her chakra isn't that powerful as Itachi's.