diff --git a/__main__.py b/__main__.py
index 032fb42..1309361 100644
--- a/__main__.py
+++ b/__main__.py
@@ -99,8 +99,8 @@ def main():
             pretty_alg.extend(solution.alg)
             if solution.post_auf:
                 pretty_alg.append(solution.post_auf)
-            if solution.mc:
-                pretty_alg.append("M")
+            if solution.post_ams:
+                pretty_alg.append(solution.post_ams)
             pretty_finger_tricks = build_pretty_string_from_finger_tricks_with_regrips(
                 finger_tricks
             )
@@ -116,6 +116,7 @@ def main():
                     "raw_alg": " ".join(solution.alg),
                     "pre_auf": solution.pre_auf,
                     "post_auf": solution.post_auf,
+                    "post_ams": solution.post_ams,
                     "finger_tricks": pretty_finger_tricks,
                 }
             )
diff --git a/cube.py b/cube.py
index 7d098d2..079a8dd 100644
--- a/cube.py
+++ b/cube.py
@@ -119,6 +119,21 @@ class LSECube:
                 return "U"
         return ""
 
+    def fix_m_slice(self) -> str:
+        match self.centers["U"]:
+            case "U":
+                return ""
+            case "B":
+                self.Mp()
+                return "M'"
+            case "D":
+                self.M2()
+                return "M2"
+            case "F":
+                self.M()
+                return "M"
+        return ""
+
     def alg(self, alg: str):
         move_functions = {
             "U": self.U,
diff --git a/move_score_approx.py b/move_score_approx.py
new file mode 100644
index 0000000..e1ef325
--- /dev/null
+++ b/move_score_approx.py
@@ -0,0 +1,72 @@
+"""
+use least squares to estimate the time it takes for each move.
+to use this, you can start a cstimer session of M and U moves (3x3x3 substes -> roux generator) and time how much time it takes you to scramble each scramble.
+you can then export the session and paste the times to this script.
+this is experimenal and deosn't work very well
+"""
+
+from typing import List
+from dataclasses import dataclass
+from collections import Counter
+from typing import List, Dict
+import numpy as np
+from scipy.linalg import lstsq
+
+POSSIBLE_MOVES = {"M", "M2", "M'", "U", "U'", "U2"}
+
+
+@dataclass
+class Solve:
+    scramble: List[str]
+    time: float
+
+
+def multiline_input() -> List[str]:
+    print("Enter/Paste your content. Ctrl-D or Ctrl-Z ( windows ) to save it.")
+    contents = []
+    while True:
+        try:
+            line = input()
+        except EOFError:
+            break
+        contents.append(line)
+    return contents
+
+
+def parse_cstimer_session_solves(lines: List[str]) -> List[Solve]:
+    solves = []
+    for line in lines:
+        if line:
+            parts = line.split()
+            time = float(parts[1])
+            scramble = parts[2:]
+            solves.append(Solve(time=time, scramble=scramble))
+    return solves
+
+
+def approximate_move_times(solves: List[Solve]) -> Dict[str, float]:
+    times = []
+    move_counters = []
+    for solve in solves:
+        times.append(solve.time)
+        move_counter = Counter(solve.scramble)
+        for move in POSSIBLE_MOVES:
+            move_counter[move] = move_counter.get(move, 0)
+        print(move_counter, solve.time)
+        move_counters.append(list(move_counter.values()))
+
+    x, _, _, _ = lstsq(move_counters, times)
+    move_times = {}
+    for i, move in enumerate(POSSIBLE_MOVES):
+        move_times[move] = x[i]
+    return move_times
+
+
+def main():
+    session_times_raw = multiline_input()
+    solves = parse_cstimer_session_solves(session_times_raw)
+    print(approximate_move_times(solves))
+
+
+if __name__ == "__main__":
+    main()
diff --git a/solver.py b/solver.py
index acc07db..7f8937f 100644
--- a/solver.py
+++ b/solver.py
@@ -4,7 +4,6 @@ import copy
 
 from dataclasses import dataclass
 from cube import LSECube, condense_algorithm, reverse_algorithm
-from eolr import eolrb_solved
 from typing import Dict, List, Tuple
 
 
@@ -13,7 +12,7 @@ class EOLRBSolution:
     alg: List[str]
     pre_auf: str
     post_auf: str
-    mc: bool
+    post_ams: str
 
 
 def lse_brute_force_generator(max_length: int):
@@ -80,19 +79,23 @@ def solve_eolrb(cube: LSECube, prune_table: Dict, solve: int):
         c.alg(" ".join(moves))
         if c.eolrb_hash() in prune_table:
             for prune_solution in prune_table[c.eolrb_hash()]:
+                # TODO: split this function, very ugly copies and very long
+                prune_cube = copy.deepcopy(c)
+                prune_cube.alg(" ".join(prune_solution))
                 alg = condense_algorithm(moves + prune_solution)
                 # TODO: this is very weird
                 for _ in range(5):
                     alg = condense_algorithm(alg)
+
                 if len(alg) > 2:
-                    # TODO: check if this is mc
                     pre_auf = ""
                     if alg[0].startswith("U"):
                         pre_auf = alg.pop(0)
                     post_auf = ""
                     if alg[-1].startswith("U"):
                         post_auf = alg.pop(-1)
-                    yield EOLRBSolution(alg, pre_auf, post_auf, False)
+                    post_ams = prune_cube.fix_m_slice()
+                    yield EOLRBSolution(alg, pre_auf, post_auf, post_ams)
         # for auf in ["U", "U2", "U'", ""]:
         #     c = copy.deepcopy(cube)
         #     auf_alg = f"{' '.join(alg)} {auf}"