In this paper we consider the following property: (⊛ Da) For every function f : R × R −→ R there are functions g 0 n , g 1 n : R −→ R (for n < ω) such that (∀x, y ∈ R)(f (x, y) = n<ω g 0 n (x)g 1 n (y)). We show that, despite some expectation suggested by [Sh 675], (⊛ Da) does not imply MA(σ–centered). Next, we introduce cardinal characteristics of the continuum responsible for the failure of (...