The held test read the X-ray gradient alone. At the floor, an atom whose X-ray term pushed
outward but whose restraints pulled it back in more strongly was held fixed against the total
target, and one whose restraints pushed it out was handed a gradient along the direction Set()
clamps away - a flat direction for L-BFGS, failed line searches and s.y <= 0 pairs.
On the 14 parity sets (--mode refine, GPU) the refined models are md5-identical; on the four
5f6m MD starts R-free 0.1707/0.1676/0.1720/0.1669 -> 0.1707/0.1690/0.1719/0.1668 (median
0.1692 -> 0.1699).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015CeEGgpKdfkCTJb3YNMJcu
(cherry picked from commit 2f4b0b5ea54fdac54de7ee6c5a1476d2fc019fd8)
leonarski_f
13bd9db55c