ExportReflections ran French-Wilson single-threaded: about 1 s on the P1 search merge of a 25k-frame
stills run (180k reflections). It now uses the merge's thread count, as AssignRfreeFlags does; both
give the same result at any worker count by construction. mtz/unmerged-mtz data, hkl, cif and report
identical (--mode scale, 25k-frame XFEL run).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>