The claim that the post-shrub region has a 368-byte period throughout is
wrong. Re-measured over the whole region the curve is flat and near noise:
stride 8 +0.027
stride 12 +0.023
stride 148 +0.009
stride 340 +0.018
stride 368 +0.018
stride 632 +0.020
Nothing peaks at 368, and the 0.1110 recorded earlier does not reproduce under
any sampling convention tried.
Where the structure is: scanning 8 KB windows at 1 KB steps for a 368-excess
above 0.15 finds one substantial region, region+41984..+57344, 15360 bytes,
plus a 4 KB patch at region+650240.
Within that window 368 is unambiguous -- +0.315 against +0.284 at 736, with
364, 372 and 732 all at noise. 41 whole records, mean 16 distinct values per
position, and nine positions exactly constant and zero: 329-336 and 340.
Twenty-five positions have 3 or fewer distinct values, clustered in 325-349,
which is a tail rather than scattered padding.
Corrected statement: a 15360-byte window of the post-shrub region is a table
of 41 records at stride 368, each with a roughly 43-byte tail whose fields are
mostly zero. The surrounding 675 KB is not that table.
What went wrong before: the original measurement was taken over a window where
368 held, then reported as a property of the region. That window holds 41 of
1841 records, and averaging it over the region flattens the peak to the noise
floor. The re-verification checked the stride but not whether it applied
uniformly, so it confirmed the number without testing the claim attached to it.