Part 1: false-positive rate (p < 0.05), no true difference, 20000 runs per row
n =  6 per group: log-rank 0.0607  Cox Wald 0.0370  Cox LR 0.0564  Cox score 0.0607
n =  8 per group: log-rank 0.0571  Cox Wald 0.0422  Cox LR 0.0536  Cox score 0.0571
n = 10 per group: log-rank 0.0566  Cox Wald 0.0457  Cox LR 0.0525  Cox score 0.0566
n = 20 per group: log-rank 0.0531  Cox Wald 0.0473  Cox LR 0.0504  Cox score 0.0531
Part 2: crossing curves (treated hazard 3x before day 20, 0.25x after), 5000 runs per row
n = 10 per group: share with p < 0.05  log-rank 0.1782  RMST(60) 0.2882
n = 20 per group: share with p < 0.05  log-rank 0.2676  RMST(60) 0.4362
n = 40 per group: share with p < 0.05  log-rank 0.4426  RMST(60) 0.6880
True RMST(60): control 35.106, treated 22.761 days