Don't forget the clear lamp has all light concentrated into a rather thin rod shaped arc, what allows way better optical control of the fixture beam.
So when such optic is used (e.g. in the form of a refractor cover or so), the clear lamp gives actually way better system efficacy (measured as the minimum illumination over a given area covered or as an area covered to given minimum illumination level, either compared towards the input power). The losses of the coated lamps go mainly on account of the light spill and uniformity.
Because the phosphor does not increase the efficacy that much (in the order of 10..20%, at best), the difference in the beam control losses does not have to be that great (even the cheap yard blasters feature a refractor redirecting mast of the light away from the wall they are assumed to be mounted on, increasing the flux forward, where the light is mainly needed; of course, that does not work with any coated lamp)...
« Last Edit: January 02, 2017, 02:08:19 AM by Medved »