How do you think Gai runs in the air? It has clearly been explained in latest chapter. He kicks the air. [
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] Without kicking the air, he can't run in the air but would be falling instead, so the picture you show him running in the air, he was actually kicking the air really fast to run circles around Madara, trying to find an opening and use his fast and devastating powerful punches.
So no, gates doesn't boost everything equally like you say. His running speed is nowhere near his punching speed just like Jubidara's running speed is nowhere near his orbs speed [
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The orbs are his fastest attacks just like the strikes in 8gates are Gai's fastest attacks
The Minato's encouragement had nothing to do with the orbs since it actually happened when Gai was in an advantageous position, kicking Madara one after another, long before Madara even thought about counter-attacking. It was just to show him they are behind him for making such an importance decision to sacrifice himself for their sake [
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And since when being encouraged in continuing your actions means you would act suicidal? You can even notice that between the time it took the orbs to reach 8gated Gai, the dude barely moved an inch despite being in a fast running movement in Madara's direction [
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So once again, the orbs are faster than 8gated Gai's movements, just like Kamui is faster than 8gated Gai's movements. Stop dreaming