docs(tools): the lectio patch exporter cannot see temporal corrections

It compares colitur's sanctoral data against lectio's calendar ini, so a
correction to a temporal day -- computed in code on both sides, present in
neither file -- is structurally invisible to it.

Not hypothetical. The Good Friday colour fix (RG 128(b) + RG 132, v0.4.0) was
missed entirely by this tool when the eight-field patch was produced, and
surfaced only by running clectio at the bottom of the chain and diffing its
output against colitur date by date. The tool narrows the search; it does not
close it.

1 files changed, 11 insertions, 0 deletions

diff --git a/tools/export_lectio_patch.py b/tools/export_lectio_patch.py
index de8a208..9942f9c 100644
--- a/tools/export_lectio_patch.py
+++ b/tools/export_lectio_patch.py
@@ -12,6 +12,17 @@ those.
 
 Every line of output names the colitur allow-list entry (C-class) carrying the
 citation, so a lectio reviewer can check the rubric rather than trust the tool.
+
+KNOWN BLIND SPOT, found the hard way. This compares colitur's SANCTORAL data
+against lectio's calendar ini, so it can only see corrections that live in
+DATA. A correction to a TEMPORAL day -- computed in code on both sides,
+present in neither file -- is structurally invisible to it.
+
+Not hypothetical: the Good Friday colour fix (RG 128(b) + RG 132, colitur
+v0.4.0) was missed entirely here, and surfaced only by running clectio at the
+BOTTOM of the chain and diffing its output against colitur date by date. This
+tool narrows the search; it does not close it. Before trusting a clean run,
+diff the two engines' actual OUTPUT for the days you care about.
 """
 import re, sys, os