Many ideas have been proposed to reduce traffic congestion problems. One of the proposed ideas is driving in platoon. Constant spacing policy is the most important control policy. It increases traffic density, but it needs very reliable communication channel. Driving with a constant time headway between vehicle is also well known policy and robust control law, but the inter-vehicle distances are very large. We have proposed in [1], [2] a modification for the constant time headway policy. This modification reduces the inter-vehicle distances largely using only one information shared between all vehicles. In this work we propose an additional modification of our control law. This modification makes our control law similar, in form, to the classical constant spacing policy, but it only uses the same shared information. This modification improves the stability of the platoon. We proved the robustness of the control law in presence of parasitic actuating lags, sensing and communication delays. This prove can be also used for proving the stability of classical spacing policy in presence of all previous delays, contrary to what have been proved in some papers in the literatures.