Lol it's kind of offensive to use my 'love' for Kishimoto's work. But I'm not that hot headed to fall by such kind of words, so I'll just skip that.
Fact is, I'm doing rebuttal in this thread because I have the conviction that Minato didn't have inconsistency after what happened in the last chapter.
- The basics, as I explained:
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- The name of techniques using the three kind of energies:
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- And the speciality: Manipulation of nature energy:
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- A perfect Sage:
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- Sage Mode is just a step. More steps - Frog-Fu:
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- In order to gather nature energy, you can't move, but you can momentarily stop and gather, meaning that once you have natural energy, it doesn't disperse at all:
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,
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,
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And last time Minato did something before awakening Sage mode was chapter 664
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And then... Obito was
walking. No one was between him and Madara. He had to waste a minimum of 8~10 seconds in this:
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And then we find
Minato who was already in Sage Mode, moving towards Madara (I assume that he is using Hiraishin):
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Conclusion:
It's clear... After Obito's battle, Minato wasn't in constant movement. So he had time doing 'apparently nothing', specially after his failed attempt to seal Yin Kurama inside Naruto... so if you link all the pieces, it's evident he had plenty of time to gather little quantities of nature energy and kneading to enter in Sage Mode. And while Obito was walking towards Madara, Minato entered Sage Mode, most likely off panel.
Also, let me be clear.
Under this point of view, your assumption of him 'moving while gathering nature energy' is contradictory to previous evidence. So, I'm not having ludicrous thoughts in this answer.

I hope I was clear. I only act and talk based on facts OR possibilities, not in emotions.
PS: And answering to the 'love' (Lol), let me be clear as well. Kishimoto isn't my favorite writer out there... I find he is regular. He bases his moves on logic, everytime I see the word 'asspull' it's because the person failed to read, he/she skipped a foreshadow/hint. BUT, Kishimoto stretches way too much his logic, making his moves being kind of unbelievable.