While I recognize the points you made that there may have been too little; thus preventing the transformation. I disagree on his being able not to balance it, partly because of a statement Juugo made (will explain later). The way it works, transformation is a direct result from not balancing it [
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Fukasaku, a teacher of sage arts, had to rely on visual appearance to know when to stop it [
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]. He has no way of knowing the amount consumed or how fast it is ingested. Consequently, since he doesn't know how much one is consuming, he doesn't have an actual idea how much is 'too much' or 'too little'
for them, he's using their features to determine this. Tranformation equals "too much" and inability for ninjitsu attacks equals "too little". My point is, it's vague.
Since transformation is a direct result from absorbing it while not knowing to balance it [
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], conversely, non-transformation/incomplete transformation/control is a direct result from balancing it (when consuming 'too much'). As I explained, Fukasaku doesn't know how much is too much, neither does Juugo [
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Since he's compatible with my cursed seal,
he should be able to handle it. This statement by Juugo is very significant, because it shows that even though Juugo may have gave Sasuke a little, he still acknowledged that little may have been too much to handle (for 'regular' people). This is what happens if one is not able to handle it
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. Even Fukasau explained that not balancing it transforms you.
So to sum that up, even if a little (which is vague), Juugo acknowledged Sasuke's ability to 'handle it'
even while in control of how much he was giving him. Absorbing it = Transformation (if not able to balance it). Juugo couldn't have been talking about his ability to absorb (since it was him that was supplying him with it), but to balance it.
Also, in case it slipped by you, Preta Path absorbing Naruto's senjutsu chakra and transforming negates the argument that he didn't change because it was already balanced for him.
Moving on; there's a second time Juugp gave him his chakra. This is significant as well, because as I mentioned earlier, Juugo made a statement that Sasuke
should be able to handle the little chakra he gave him the previous time. Yet this time, he gives him even more. Enough for the Zetsus to retreat. Why did they even retreat? Most likely, because they wouldn't have been able to handle/balance the chakra being pumped into their bodies. Note; it was enough to make ALL six of them come out [
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Orochimaru explains that senjutsu chakra is imbued into the cursed seal
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. Yet, Sasuke was still unaware that this was incorporated with the power of nature. So why would he go train at Ryuchido? In fact not only did he possess this ability, Orochimaru mentioned it right in from of him,
right after the Kabuto fight. Yet he still inquired about it in the war....we can only speculate his intentions (he may be planning something), but using his negligence to utilize it in battle or go train at Ryuchido so far isn't evidence he can't do it. Even
Juugo didn't mention or do anything after Naruto explained this.
I also like to bring up another plausible possibility -
Orochimaru. When he arrives at the battlefield, he can simply do this if need be [
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