Billy's brilliance and ingenuity eclipses the vast majority of scientists that exist in reality. It is not just his amazing memory of facts that is impressive, but also the ease with which he masters new technology, and rises to new difficulties. It isn't a surprise that once the Power Coins were destroyed, and the teens became Zeo, he was still useful as an assistant in the Power Chamber. Still, he was the longest-serving Mighty Morphin' Power Ranger. The Blue Ranger was on the team from their inception, and no one else served in his stead. Of course, it would quite difficult to try and fill his shoes.