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Fluorescent lights: full spectrum or not?

With all the email discussion on the use of cool white vs. warm white vs.
full spectrum bulbs, I thought I'd throw in a few things I learned last
year at a University of MN forum  last year on indoor seed starting.  The
discussion was held by a PhD from  the extension servces.
Light is composed of three additive primaries, blue, red, and green.
Plants absorb blue and red wavelengths, which is why they look green.  
The use of full spectrum bulbs is not critical for this reason -  plants
don't absorb full spectrum (this made sense to me, as if they did absorb
all wavelengths they'd be black).  Standard cool white (i.e., cheap)
bulbs supply light in wavelengths appropriate  to plants.  Intensity,
which follows an inverse square law,  is more important than bulb type. 
Seedlings need 16 hours per day of light, but it can be any 16 out of 24.
 They can actually be under lights 24 hours per day for up to six weeks
without problems.  Afterwards, they  need a "rest".
 I followed this advice last year and had very good luck, although, in my
limited gardening experience, there always seem to be many ways to
achieve the same end.

JRC in USDA Zone 4A (Minnesota)

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