exp+eval: 轮次51-52——2x2 补全 + 逐题老师用时落盘；1.3x 口径的时限收益其实是显著的

轮次51 (2x2 缺失格 K16+pre)：最好格 到达 0.5664 / 时限内 0.3594 / 2s误差比 0.1382 /
行程比 2.4142 / 碰撞 0 / 超VMAX 0。主效应：pre 在 K8 +6.64pp、K16 +6.25pp(时限)，
K16 在 endpoint +3.13pp、pre +2.73pp ⇒ 时限可加无交互；到达饱和(pre 在 K16 上净+1题 p=1.0)。
最好格 vs 历史控制逐题赢20丢9 净+11，McNemar p=0.061 ⇒ 到达仍未确立。

轮次52 (仪表)：dump 补 t_exp/tr_ref(题目属性，与臂无关 ⇒ 一条臂即可给全部历史臂补配对)。
改完落盘代码先自证行为未动：同配方控制臂 22/22 老键逐位相同；limit=2*t_exp 实测对上
⇒ "到达率自带 2x 时限"从推断变成实测。

逐题配对(vs K8 endpoint, 判据=ok 且 t_done<=1.3*t_exp)：
K16pre 27赢3丢 净+24 p=8.4e-6；K8pre 22/5 净+17 p=0.0015；门控5 23/6 p=0.0023；
门控20 22/6 p=0.0037；h=4 15/5 p=0.041；K16endpoint 17/9 p=0.169；h=8 11/7 p=0.481；
tie=1 3/0 p=0.25。
⇒ 自我纠正：轮次46-51 我一直拿 success(那道 2x 门)做配对，把"时限内"写成没有配对支持。
现在两栏分开：到达未确立(p>=0.06)，时限内已确立(p=0.0015/8.4e-6)。
副产物：K16+endpoint 的 +3.1pp 时限当初没有配对检验，实测 p=0.169 不显著，已在轮次52记下。

docs/experiment_round52_ctl_ex.json

@@ -0,0 +1,110 @@
+{
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