Disconfirm the ten-entry table lead from the region after shrub

Range measured: level 0, 16047040..16737344.

Treating the ten entries' low halves as offsets from the region start lands
on blocks exactly 148 bytes apart, the first nine of which begin 08 00
followed by a 16-bit id stepping by 0x40. That reads as a pointer table and
it is a coincidence.

Walking the same 148-byte stride across the rest of the region, only 14 of
4657 blocks start with 08 00. The first nine agree, then the pattern breaks
completely -- id deltas go from a steady 0x40 to 0x801, 0xf510 and
negative values.

Eight consecutive values at a constant stride is much more than chance
should produce and much less than a structure needs. The lead committed an
entry ago is therefore disconfirmed, and the region remains unidentified:
real, non-zero data, bounded, and unopened beyond its first ~150 bytes.

The open question is unchanged and is where the next attempt should start:
the 690,304 bytes on level 0 between the last shrub class and the constant
trailer.

docs/formats/core-data-regions.md

@@ -168,3 +168,20 @@ entries mean, what 148 refers to, and why there are ten, are all unestablished.
 Ten does not match any count already known for this level -- 238 moby
 classes, 74 tie, 7 shrub, 93 tfrag textures -- so this is not yet tied to any
 structure elsewhere in the lump.
+
+### Follow-up: the 148 stride is a coincidence
+
+Treating the ten entries' low halves as offsets from the region start lands on
+blocks exactly 148 bytes apart, the first nine of which begin `08 00` followed
+by a 16-bit id stepping by 0x40. That is a convincing-looking structure and it
+does not survive being extended: walking the same 148-byte stride across the
+rest of the region, **only 14 of 4657 blocks** start with `08 00`. The first
+nine agree and then the pattern breaks.
+
+So the ten entries are not a pointer table. The constant stride held for
+eight consecutive values, which is far more than chance should produce and far
+less than a structure needs.
+
+Recorded because the lead was committed as a lead and this is where it goes.
+Nothing else about the region has been identified: it is real, non-zero data
+of unknown type, bounded, and unopened beyond these ~150 bytes.