Notice that the attractor for this model encloses more space than that of the first driven pendulum. Check the Phase Space Projection, or the Phase Space Orbit views to see this. The volume of phase space enclosed by an attractor is an indicator of the steady state energy of the system. In this case energy is being added at a faster rate because each kick is more energetic, so the internal energy of the system increases until the leakage of energy matches the rate at which it is being added. In this model the kicks deliver enough energy to be clearly visible in the phase space projection view.
Now go back and look at the real space view. It is pretty clear the requirement we laid on early in the discussion that the pendulum swings remain small has been violated. To see if that has any significance, let's consider the implications of timing our pendulum kicks at some regular interval, not on the basis of pendulum position as in the last two models we ran.