tent, three-point, pairs (without A -> with A):  APS | CHA | both | flat fun3-6 sum
  defect        credit    3545->4134   2949->2926   6494->7060  1044->993  solved 193 over 0
  plain         credit    3568->4130   3020->2986   6588->7116  1044->988  solved 193 over 0
  dissim+slope  credit    3857->4223   3002->2947   6859->7170  1043->1002 solved 193 over 0
  slope         credit    3507->4121   2997->3007   6504->7128  1051->1007 solved 193 over 0
  shape+slope   credit    3755->4169   3021->3059   6776->7228  1064->1064 solved 193 over 0
  defect        none      2523->3180   4198->3508   6721->6688  2806->2081 solved 188 over 1
  plain         none      2806->2967   4104->3471   6910->6438  2707->2070 solved 188 over 0
  dissim+slope  none      2726->2859   2785->2545   5511->5404  1376->1157 solved 193 over 0
  slope         none      2848->2971   3075->2735   5923->5706  1710->1331 solved 193 over 0
  shape+slope   none      2675->2930   5443->5452   8118->8382  4000->4000 solved 173 over 0
  defect        project   2523->3180   3210->2954   5733->6134  1818->1527 solved 193 over 0
  plain         project   2806->2967   3220->2925   6026->5892  1823->1524 solved 193 over 0
  dissim+slope  project   2726->2859   2785->2545   5511->5404  1376->1157 solved 193 over 0
  slope         project   2848->2971   3074->2735   5922->5706  1709->1331 solved 193 over 0
  shape+slope   project   2675->2930   3498->3506   6173->6436  2055->2054 solved 193 over 0
  defect        safe      3131->3207   3368->3386   6499->6593  1943->1929 solved 193 over 0
  plain         safe      3036->3171   3363->3389   6399->6560  1950->1931 solved 193 over 0
  dissim+slope  safe      3123->3170   2683->2710   5806->5880  1228->1248 solved 193 over 0
  slope         safe      3020->3187   2903->2895   5923->6082  1484->1469 solved 193 over 0
  shape+slope   safe      2527->2986   3108->3223   5635->6209  1629->1687 solved 193 over 0

VERDICTS for the proposed rule (tent, 3-point, projection)
  X1 CHA < 3220:       2925  ->  PASS
  X2 APS <= 2806:      2967  ->  FAIL
  X3 guarantee family with A: 0 violations over 39 cells; cells solving < 193: 0  ->  PASS
  X4 flat fun3-6 sum:  1823 -> 1524  ->  PASS
  X5 best pair with A over both sets: pure+dissim+ext+slope.ratio.derived3.project 2859+2545=5404  (reference 5511, Chandrupatla 5228)
  proposed + A vs Chandrupatla, APS: 42/62/49  sign p=0.53  totals 2967 vs 2787
  proposed + A vs Chandrupatla, CHA: 11/1/28  sign p=0.0095  totals 2925 vs 2441

nine functions, three-point, projection, no readings (without A -> with A), both sets:
  cbrt         17993 ->  18181
  cosine       19784 ->  19753
  exp_abs       6652 ->   6869
  exp_sq       19786 ->  19780
  rat_sq       19793 ->  19796
  ratio         6026 ->   5892
  ratio_soft    9352 ->   9285
  rational      6823 ->   7483
  sqrt         13381 ->  13633