First, the evidence. Open this pic in a new window; file size is prohibitive for 56k users, maybe:
http://img104.imageshack.us/img104/2037/prooflr4.gifWhat's happened? Serge's rear end has been mapped to his belt buckle quads, and his belt buckle has been mapped to his rear end quads! Here's what I did:
BELT BUCKLE UV and NON-UV DATA: REAR END UV and NON-UV DATA:
-U1 V1 U2 V2 U3 V3 U4 V4 -U1 V1 U2 V2 U3 V3 U4 V4
aa aa aa aa aa aa aa aa-U1 V1 U2 V2 U3 V3 U4 V4 xx xx xx xx xx xx xx xx-U1 V1 U2 V2 U3 V3 U4 V4
bb bb bb bb bb bb bb bb yy yy yy yy yy yy yy yy
NOW, SWITCH NON-UV DATA LIKE SO...
-U1 V1 U2 V2 U3 V3 U4 V4 -U1 V1 U2 V2 U3 V3 U4 V4
xx xx xx xx xx xx xx xx -U1 V1 U2 V2 U3 V3 U4 V4 aa aa aa aa aa aa aa aa- U1 V1 U2 V2 U3 V3 U4 V4
yy yy yy yy yy yy yy yy bb bb bb bb bb bb bb bb
See what I did? Leaving the UV maps for Serge's rear end and belt buckle alone, I swapped the non-UV data corresponding to those pairs of quads. If doing this switched which texture pieces are mapped to which polygons, we have the following for Section 1-2's quad data structure:
So basically, there's a UV map followed by a pointer to the polygon that UV map "maps" to!
If this makes sense to others besides myself, it shall be added to the wiki.
HOWEVER -- we are not finished with Section 1-2 yet! We must figure out the purpose of the non-quad (possibly triangle, possibly something else) data that occupies offsets 0x358 ~ 0x0FB8 in Serge's model data! Thus will begin my next series of experiments.
ADDENDUM: 403 rows of data for 403 quads on Serge, by the way. The quad data occur between offsets 0x0FB8 ~ 0x28E7 for 6448 bytes in decimal. Divided by 16 bytes per quad (8 bytes for each UV map, followed by 8 bytes for each polygon pointer), that makes 403 rows and 1612 vertices, just as Luminaire said earlier.