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We can simplify this problem a bit and attach some actual numbers using the Work-Kinetic Energy Theorem to get a general idea if it's worth rolling through or not. Assuming a weight of 1850 kg (the lightest trim of the 2006 Highlander Hybrid, yours may actually be heavier), a speed limit of 25 mph (11.1 m/s), and a difference of 0 mph (full stop) versus 1 mph (0.444 m/s rolling through):
Work (W) = Kf - Ki
K = (1/2)mv^2
Kf = (1/2)(1850 kg)(11.1 m/s)^2 = 113969.25 J = 114 kJ
Ki,rolling = (1/2)(1850 kg)(0.444 m/s)^2 = 182.3508 J = 0.182 kJ
Ki,stop = (1/2)(1850)(0 m/s)^2 = 0 kJ
Wrolling = 114 kJ - 0.182 kJ = 113.818 kJ = 114 kJ
Wstop = 114 kJ - 0 kJ = 114 kJ
So you can see, the difference is within rounding error to 3 significant figures. However, that 0.182 kJ does equal 0.05056 Wh, out of 33.1 kWh in one gallon of gasoline--or 0.0000015% of a gallon. You would need to roll through approximately 654,725 stop signs at 1 mph to save one gallon of gas, and that's assuming 100% conversion efficiency.
There are much easier, legal ways to save one gallon.
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