*SSSWHHOOOOSSSHHH
ok back!
DISCLAIMER: S. List was before my time as projectionist so i never actually held a print. (thank goodness cus it was huge

)
But I saw it on the theater (yeah and like that just makes me an expert

) (well it helps) and I read what was an article on American Cinematographer about this and well, with a little knowledge about photography and how film types work...
here deathie's take on this
the film was shot parts in true b/w and parts on the grey-color dye negatives and some in true color (3 color?

) .. I think maybe the intermediates were then made onto color-grey dye stock and/or actually I think the film print, or any step after the first intermediate stage, could have been printed in regular 3 color layer stock (I remember the film had lots of sections (if not all) that had slight color cast (or what's called color crossover) cus the highlight tones were in a slightly diferent color tone than the shadows, etc. That doesn't happen with silver b/w film cus it's all silver and that is the same uniform color from white to black.
True b/w negative has a different look than "grey color" negative, it's sharper, granier, specially in the highlights, but at the same time basically grain free in the shadows; it's quirky (it's tonal curve usually is not a straight line) and this, and it's contrast, can be easily changed during developmnt or after it chemically. "Grey color" on the other hand behaves exactly like color film: is smoother, less sharp, has less grain, the highlights specially are almost grainless cus dyes end more like solid color in those highlights (and we see tonal differences better in highlights, and grain, really being micro minute size tonal differences, we better have it on the other side, the shadows.) and it also has a straight tonal curve that doesn't varies cus that's the way color film is designed: to have all within tolerance: shadows, midtones, and highlights, 3-color film (which actually has several color layers), has to mantain all those layers exactly the same, to avoid color crossovers, and uses a very strick controlled development, so results are accurate and repeatable.So that's why films like Ilford XP1? (it probably is called different now) and the Kodak equivalent are now sold more than true b/w films, like T-Max etc, SPECIALLY cus you can develop it in the color developing line in the lab which is the more common one used today. So that alone might make it cheaper than making special one shot b/w prints. They are just color prints. Without color.
There's another issue, and this is in Projection. (part of it I talked already in the heat melting post

) That issue is, that color dye film has the same contrast in any projector cus the dyes are just transparent groovy color dyes. Silver prints and negatives behave different when seen or printed under different lights, having more contrast the more pinpoint-like the light source shining through them is. (Called the Callier Factor in photography, sillver scatters light instead of being transparent) So you have to keep track of this when printing/projecting or your contrasts will change. Printing onto color-grey dye stock, o printing the b/w negatives onto color stock stops this variance right there as the color dye stock from then on behaves with one contrast. (The only problem of printing b/w negatves into color stock is you have to color balance them so they end up looking grey/neutral. Here's where color grey intermediates help.
It could go like this:
{b/w negative(varialble contrast)+ colour negative (standart contrast)+ "grey color" negative (standart contrast)} --->all printed onto grey color interpositive (except the pink girl)--> after that all printed into color internegative ---> printed into standart color prints
Thats one possible way to do it.
All this leads to better consistency and repeatability
Another thing is, that tho true b/w film is sharper (up to 200 cycles/mm) and grainier, than color negative (usually 100 c/mm) , well, and from what i've seen in Kodak's data sheets, color intermediates and prints are much sharper (some 500 c/mm) and much much less grainier than b/w intermediates (which some are about as sharp as the b/w negative film or worse) So actually printing b/w negatives onto dye based intermediates and prints should give better results than true b/w silver prints in that department. Spielberg's Cinematographer seems to have experimented and discovered all this while doing pre-production and during production of the film (i think he said something in the article like he was experimenting with it or something cus he had never done this before to get the right looks for each section)
dm already knew all this from reading photography books and data sheets and was very satisfied to read someone had confirmed in practice his theoretical conclusions.

Marmalade was happy.
I hope i didn't leave anything out.
I didn't use the caculator this time ehh?
(You don't want deathie talking about dLog values (logaritmic densities), obsolete gamma, and the Contrast Index

)
and AWAY i go again.
Duty never stops
*WWWHOOOOOSSHHHHHHH
RE-REMouSeTERED now that I had time. All crazy in a rush typos corrected. (I think) Now it (almost) makes sense. I hope
------------------------------------
deathie mouse. more than you want to know