[aardvark291]

I hope you mean x (multiplication) rather than ^ (exponentiation). If we're talking about fanout (each of 10 items of has 10 subitems, each of which has 10 subitems), multiplication is the relevant operation. And 10^(10^10) or (10^10)^10 is a hopelessly, uselessly, inconceivably large number. (Exponentiation is not associative; 3^(3^3)=3^9= 19683 while (3^3)^3=9^3=729.)

[AlexCoventry]

I took it to mean something fairly vague about potential super-exponential blowup in the complexity of the states you have to reason about, when you have to reason directly about third-order effects in a code base.