If we're fighting, say, Konan, who we can't kill in a single strike, and she goes full Bullet Hell with her paper so that we have to dodge over and over again... We can afford to dodge about 250 times, if we use no extra chakra on anything. Summon help? Whoops, suddenly we've got 100 dodges. Use our ninjutsu? Blam, only 50 dodges left.... Then 10... And then we get to the point where we can't dodge any more, because we used up all our Chakra.
First problem: you're comparing a B-rank combatant against an S-rank combatant.
Second problem: you've decided we're using a shitty defense against our opponent to begin with. Paper is flammable, and wind fucks over physical projectiles.
Third problem: your example ignores things like "summons also have chakra they can spend to defend us".
Fourth problem: why the fuck are you focusing on dodging to the point of excluding
ending the need to dodge in your scenario?
I can't help but think that the application with 1/50th the chakra cost has around 1/50th the durability. Shunshin is still my choice due to it's general utility, but I don't think we can say that the temporary barrier solves our squishiness - it almost certainly can't handle the high-end bullshit we face.
I'd say the application of the same seal that costs 1/50th the chakra is probably something like 1/50th the size, actually. Partially because that's kind of explicit, and there's no implication of a difference in durability.
I'm mostly just laughing that everyone has convinced themselves that the technique that's not meant for dodging is going to be better at letting us dodge than the technique specifically meant for the purpose of making us better at dodging.
... I'm not sure where you're getting people saying it's better at
dodging than the one meant for dodging. I'm only seeing arguments that it's a better fit for what we're doing. And that improving our offense and maneuverability in addition to our defense is better than
just improving our defense.
...Given that at several points in that video, the bullets are the background, I don't think going full Touhou is possible in the Naruto universe. I mean, we could try to drive Naruto to be the harbinger of projectile hell via Shadow Clones, but outside of that I don't think there's anyone in the Naruto universe able to go Touhou on the attack.
Tenten, though she has a glaring weakness to heavy winds. Like we can generate pretty easily.
And... Really, anyone who can quickly pull large numbers of projectiles out somehow (like from storage scrolls) could do the same.
Dodging Btw Raindrops costs no chakra, allows us to dodge single attacks, but has no defense against AoE.
We don't actually know that.
And you make my point for me by literally arguing that the multipurpose technique will be better at dodging than the dodging-specific technique is!
It slices! It dices! It juliennes! It's the SHUNSHIN!
You really shouldn't read so heavily into someone saying that the Shunshin is better at a
specific application of dodging. Saying I'm better at geometry than you isn't the same as saying I'm better at math than you.
