Originally Posted by John Korling:
Sometimes the overall glossy effect doesn't "scale down" well on miniatures of the real thing. A number of factors play into this, such as lighting and overall surface area that the light hits. While the prototype looks glossy, the same amount of gloss on the model can make it look more toyish than realistic.
As to whether or not one chooses to take fixed pilot models and do the relatively easy wheelset swaps, that's a personal choice not to do so, and it certainly does not invalidate the fact that the fixed pilots are far more realistic than swiveling pilots.
Gloss depends upon surface morphology of the binder/pigment system, critical pigment volume concentration (CPVC) and incident angle and it is these physical constraints that determine the specular reflection. These values are completely independent of scale. Thus, 60 deg. gloss, 85 deg. gloss so on and forth are the same value whether something is 1/4" scale or 1:1.
So while there are scales to measure gloss, there is no scale to gloss in the context of model railroading.