Rework check/pawn-push/recapture extension gating on real SEE (GetMoveSee, generalized from GetCheckSee), restrict LMR to leftover moves only, and tighten recapture's window back to 1x after measuring a 6.8x node blowup from sharing the wider window.

Head-to-head match at 1170 games confirms parity with the prior head (score=0.510, LLR still between bounds) -- landing as a neutral-or-better baseline rather than a regression.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/root.c b/src/root.c
index 46a7a80..f5fe4c1 100644
--- a/src/root.c
+++ b/src/root.c
@@ -598,6 +598,9 @@ Return value:
 #endif
     Trace("Extensions: (%u +, %u q+, %u 1mv, %u !kmvs, %u mult+, %u pawn\n"
           "             %u threat, %u zug, %u sing, %u endg, %u bm, %u recap)\n"
+          "             check by amount (1/4,1/2,3/4,1 ply): %u %u %u %u\n"
+          "             1mv by amount (1/4,1/2,3/4,1 ply): %u %u %u %u\n"
+          "             pawn push by amount (1/4,1/2,3/4,1 ply): %u %u %u %u\n"
           "             %u / %llu qsearch nodes (%.1f%%) were in-check "
           "evasion nodes\n"
           "             too-deep bailout: %llu ply-limit, %llu "
@@ -614,6 +617,18 @@ Return value:
           ctx->sCounters.extension.uEndgame,
           ctx->sCounters.extension.uBotvinnikMarkoff,
           ctx->sCounters.extension.uRecapture,
+          ctx->sCounters.extension.uCheckByQuarterPly[1],
+          ctx->sCounters.extension.uCheckByQuarterPly[2],
+          ctx->sCounters.extension.uCheckByQuarterPly[3],
+          ctx->sCounters.extension.uCheckByQuarterPly[4],
+          ctx->sCounters.extension.uOneLegalMoveByQuarterPly[1],
+          ctx->sCounters.extension.uOneLegalMoveByQuarterPly[2],
+          ctx->sCounters.extension.uOneLegalMoveByQuarterPly[3],
+          ctx->sCounters.extension.uOneLegalMoveByQuarterPly[4],
+          ctx->sCounters.extension.uPawnPushByQuarterPly[1],
+          ctx->sCounters.extension.uPawnPushByQuarterPly[2],
+          ctx->sCounters.extension.uPawnPushByQuarterPly[3],
+          ctx->sCounters.extension.uPawnPushByQuarterPly[4],
           ctx->sCounters.extension.uQExtendChaseNodes,
           ctx->sCounters.tree.u64QNodeCount,
           (ctx->sCounters.tree.u64QNodeCount ?