1. Yes, why?
Tobi did see the kunai he just didn't try to dodge it, he could have.
2. Give me a pic of Minato's using the sage frogs and we're good

Those fanboys were inventing things we've never seen Minato using so we assumed Sasuke has perfect susanoo.
3. "quickly lose chakra" are you kidding me, do you even know how big sasuke's chakra reserves are? You one-sided fanboy.
4. Amaterasu instantly burns the target, the bijuu dama add to make contact to deal damage, the amaterasu is instant, the frog will already be dead before he gets to seal it (and that's if he can, LMAO)