 It is difficult to resolve the controversy because proper controlled experiments are nearly impossible, but work performed by Charles B. Moore, et al., in 2000 has shed some light on the issue, finding that moderately rounded or blunt-tipped lightning rods act as marginally better strike receptors.As a result, round-tipped rods are installed on most new systems in the United States, though most existing systems still have pointed rods.According to the study,

In addition, the height of the lightning protector relative to the structure to be protected and the Earth itself will have an effect.