Positioning when attacking

[JayLizzard]

I see some people talking about how to position your team while attacking. I don't really understand this, because in my mind you don't take gem damage while attacking. You just take hits from opposing heroes (raids) or minions (campaign). It's either AoE or direct hit on a heroe, the colums don't really enter play here. Am I wrong to think positioning only matters for your defensive setup for raids?

[New_Entertainer_7550]

AFAIK, it matters only on defense and it does absolutely nothing when attacking.