Oh right, that's what's being meant. I confused it with constant time as in O(1). Wouldn't most implementations of fixed length integers have constant time tho

Oh right, that's what's being meant. I confused it with constant time as in O(1). Wouldn't most implementations of fixed length integers have constant time though? It barely seems worth optimizing unless your integers vary massively in size, at which point using fixed size integers is clearly suboptimal.