Particle orbits and the Rosenbluth–Hinton residual zonal flow are evaluated for the case of a strong equilibrium radial electric field Er = −(dϕ/dψ)|∇ψ|as observed in a tokamak pedestal. The ordering used is Er ∼ Bpvi/c, where Bp is the poloidal field and vi is the ion thermal speed. The earlier calculations of Kagan and Catto for this regime (2009 Phys. Plasmas16 056105) correctly describe the effect of a uniform dϕ/dψ, but not the 'orbit squeezing' effects associated with electric field shear d2ϕ/dψ2 (Kagan and Catto 2009 Phys. Plasmas16 099902). The present paper gives the corrected dependence on electric field shear for a quadratic equilibrium potential ϕ(ψ). Analytical results are given for the large-aspect-ratio limit and a numerical approach is outlined for performing calculations at finite aspect ratio.