Why do people not understand A8?

[Nanaho]

I got a tank mate who din't know how to tank swap... it's the first time we got it in a casual content ?^^
you can't fight against it's a new content, just try to explain and then try.
It happen also with A4 in 3.0.
Also GG SE this A8 is a so epic fight XD.

honeslty, i've cleared this fight like 9 times now, and i still dunno what this tank swap mechanic is people keep mentioning ? >....>; ive never died in there, so i have no idea..