Clear/white lighting is useful in specific applications, such as distance ROW, and intersection ROW. A bit of clear strobe or LED to the rear, ie; HAW strobe or LED in the reverse lights, is a nice attention grabber. Strobe and LED in clear tend to come off with a hint of blue, and blue being the best color to penetrate fog and rain is perfect for blocking. The small application of HAW's give just enough pop, but not so much as to be blinding. To the front, to much clear washes out the emergency color. Running with take downs on (or other steady clear) next to red or blue will drown out the color. Dallas Police have a policy against running code with TD's and Alley lights on, and you fail PVOC if you run the course with them on. Years ago, a motorist refused to stop for a DPD car (equipped with a StreetHawk) for almost 10 miles. The news even got set up and had great video from an overpass. Once stopped, the motorist claimed that she did not know it was a Police car, and thought it was some guy in a pick up with flood lights. The Officer had his TD's and spot light on, and had turned the TD's on with the r/b's. She was charged with fleeing, but the case was dismissed when her lawyer played the video from the news. The video showed her car, and a large blob of white light behind her, with no signs of red or blue light. She also claimed that she could not hear the siren due to her windows being up and driving at highway speeds. She took the 70 in a 55 ticket and went on with life.
In a FD setting HLF's and clear lights reflect the smoke, haze, and mist at fire scenes, blinding or reducing visibility, which is the primary reason NFPA went with the white shut of in park standard.
When I was in traffic control, my last vehicle was a 2000 Explorer, I had HAW strobes in a X pattern set in the amber turn signals and back up lights. Very effective.
