Hesitation

Excessive absorption of Natural Energy would indeed cause it to backfire.

But exactly where the boundary of "excessive" lay was impossible to know.

That was because it varied from person to person.

However, Qi Shuang could confirm that Madara Uchiha could not use Senjutsu. Thus, he had no way to control the Natural Energy absorbed from Qi Shuang and could only seal it within his body.

This created a distinction between ordinary sages, who used Natural Energy directly, and Madara, who stored it through sealing.

Because he did not use it, Natural Energy posed a far smaller threat to Madara Uchiha. Naturally, the upper limit of sealed storage was also higher than the upper limit of an ordinary sage's usable reserves.

Therefore, Qi Shuang was certain that even if he transferred all his Natural Energy to Madara Uchiha for absorption, it would never be enough to trigger petrification through backlash.

This had also been partially confirmed by the story from his previous life.

He clearly remembered that, in that story, Naruto Uzumaki had sent Natural Energy into Preta Path Pain for absorption, defeating Preta Path Pain through the backlash of the Natural Energy.

During that process, Naruto Uzumaki's sage markings had faded and reappeared several times in succession.

That meant Naruto Uzumaki had entered Sage Transformation several times during the process, and the Senjutsu Chakra produced after each transformation had been completely absorbed.

In other words, to kill Madara Uchiha through petrification caused by backlash, the Natural Energy absorbed in a single Sage Transformation by Qi Shuang was nowhere near enough.

He needed to undergo Sage Transformation multiple times, then supply the resulting Senjutsu Chakra for Madara Uchiha to absorb before he could achieve his goal.

Multiple Sage Transformations meant a prolonged battle.

Moreover, repeatedly absorbing Senjutsu energy was not