Just for fun: Can you guess how I did this?

Question

A few months ago a thread here discussed different way to stroke 3D objects in After Effects.  There were lots of clever suggestions.
I made a TV spot last week that uses growing 3D ribbons to spell out the 2012 in the product title.  There are straight planes and curves within the ribbon paths, and lighting and shadows were required to match the original album art it replicates.  I needed to get the job done quickly and didn't have time to use a 3D application, so I used (what I think) was a rather innovative approach.
So, for a bit of fun, can you pick how I did this?  The project is created entirely in AE, in one composition. 
Apologies for the heavy compression in the video.

Answer 1

Thanks Todd!
My first attempt was exactly Rick's, using stacked solids with Stroke applied.  I gave up on it because, once shadows were applied, the "ribbons" seemed to develop a mottled texture, presumeably because each layer in the stack casts a shadow on the layer behind it.  Using Rick's design above, here's an example:
So in the end, I used text layers!  Each ribbon is simply a long string of Helvetica "I" characters, with their kerning pulled back so all the characters touch.  Convert to per-character 3D, rotate X axis 90 degrees, and apply mask as text path.  Then I use a simple Text Animator on opacity to draw the lines on or off. 
The great advantage of this is no cumbersome stack of layers.  Each colour is one layer, so there's just five layers in my comp for each object. The "20" is one object, then the "1", then the "2" - 15 layers in all for the whole thing.  Changing colours is as easy as changing a single text layer.
A total render hog, all the same:  it took 11 hours to render the 15 second spot, on an 8 core Mac Pro with 16GB of RAM.  But in 3D Draft mode the comp was surprisingly easy to work with.  It's just the lighting and shadows that slow things down.
Anyways, perhaps this may inspire someone else to do something interesting with text layers.