Agreed - the majority of drivers will now be making the discrete decision "Is green or amber" not "Is amber or red".
That is to say, that the proportion of drivers having to make the risky decision (i.e. if they were to decide to accelerate through the amber) is significantly reduced... although interestingly I think the principle states that as T(amber) << T(green) the liklihood of indecision for that second case now does increase.