Dynamic modes in projectors cause them to become more green, yellow, and blue usually. Though some dynamic modes just boost gain and saturation way off the chart and cause a more cartoony look. I would say that the Epson's dynamic modes makes some colors look more saturated and others less so.
I'm not a physicist, but I'll do my best (apologies if I make a mistake)... This is going to sound really nerdy, and sometimes I dislike physics because there are too many If's, And's, and But's....
I had to read a refresher course real fast on a wiki, but here it goes...
Light is basically pulsating energy (like a ripple wave of energy traveling at a constant speed until it hits a different surface or medium). The intensity of the light is formed by the density of the photons (which is what causes brightness, this is basically energy particles).
So you basically have:
Photons - Energy and intensity (The energy source that creates light)
Wavelengths (the measurement of the wave of a light, the length between the peaks and valleys of the wave)
Frequency - How fast the peaks and valleys pass between each other, but this is not related to speed as much as it is related to the curvature of the wave
You can describe light as a frequency or wavelength without specifying both measurements, since the two measurements are proportional to each other.
A projector lamp is emitting certain frequencies but not all evenly (though LED's are purer white than UHP's from my understanding), as the UHP lamp ages the spectral characteristics of the frequencies it emits change due to the age. A lamp that has the best spectral balance would generally have the least amount of difference in brightness between BEST mode and BRIGHTEST mode, because it is emitting the different spectrums of each visible light somewhat evenly (each wave peak on the visible light spectrum is peaking at about the same height on all the spectral colors). The closer the lamp is to spectral purity, the closer it's natural emitted color is to pure white, which I believe is a good thing.
It can be difficult to understand light in the terms of frequencies, so the best way to think about it is by comparing it to sound. Hence, think of pure white light as the entire rock band playing at the same time (hence all the frequencies, low freq drums, higher guitars, etc...). To disperse or separate a frequency of color from the white light, we'd have to get any one of the musicians playing solo without any other instruments in the background. For light this is done by isolating the spectrum by using either an additive or subtractive method or dispersion.
A spectral color is a color that can be defined INDIVIDUALLY by a single frequency derived from white light (hence a guitar player is a spectral form of light because it is a unique instrument). A guitar player + drums is not a spectral form of light, because it is a combination of frequencies. Black and white are not colors and not spectral, white is the entire band and black is the absence of photons or the absence of light entirely.
There are only so many spectral formations of light (actual frequencies) that translate to visible light in how we can decipher them. We can create spectral colors with non-spectral mixes and our eyes cannot usually tell the difference.
What this theory tells me is that at some point there are diminishing returns to enhancing spectral fluidity of the color waves, because contrast would have a much greater affect to how we perceive color once we get the spectral variations isolated to the point of close enough.