diff --git a/rugnux/Rugnux.cpp b/rugnux/Rugnux.cpp
index 64980519..cf3b0308 100644
--- a/rugnux/Rugnux.cpp
+++ b/rugnux/Rugnux.cpp
@@ -40,6 +40,7 @@
 #include "../image_analysis/lattice_search/LatticeSearch.h"
 #include "../image_analysis/scale_merge/TwinningAnalysis.h"
 #include "../image_analysis/scale_merge/HKLKey.h"
+#include "../image_analysis/scale_merge/ScaleOnTheFly.h"
 #include "../image_analysis/scale_merge/StillsPartialityRefine.h"
 #include "../image_analysis/WriteReflections.h"
 #include "../image_analysis/bragg_integration/CalcISigma.h"
@@ -1127,6 +1128,13 @@ ProcessResult Rugnux::RunPipeline(RugnuxObserver *observer, bool write_output, b
                 StillsPartialityRefine refiner(experiment_);
                 const double mean_tilt = refiner.Run(indexer->GetIntegrationOutcome(), config_.nthreads);
                 logger.Info("Stills partiality post-refine: mean |dpsi| = {:.3f} deg", mean_tilt);
+                // The refine fits its OWN per-image scale, with no floor, and adopts it unconditionally
+                // when the image has no prior CC - which is exactly the state the guard above leaves. So
+                // the guard was protecting nothing: measured on a jet dataset, of 367 images it left
+                // unscaled only 8 were still unscaled in the output, and 53 reached the merge at or below
+                // a fiftieth of the run median, the worst at a 4525th. Whatever produced the final scale,
+                // it is the final scale that has to be credible.
+                ScaleOnTheFly::RejectCollapsedScales(indexer->GetIntegrationOutcome());
             }
             const std::vector<IntegrationOutcome> &merge_input = indexer->GetIntegrationOutcome();