diff --git a/src/segmentation_skeleton_metrics/data_handling/graph_loading.py b/src/segmentation_skeleton_metrics/data_handling/graph_loading.py
index f3591f7..ea4a608 100644
--- a/src/segmentation_skeleton_metrics/data_handling/graph_loading.py
+++ b/src/segmentation_skeleton_metrics/data_handling/graph_loading.py
@@ -498,9 +498,7 @@ class LabelHandler:
         Labels that are allowed to be assigned (after filtering).
     """
 
-    def __init__(
-        self, labels=set(), label_pairs=set(), use_segment_mapping=False
-    ):
+    def __init__(self, labels=set(), label_pairs=set()):
         """
         Instantiates a LabelHandler object and optionally builds label
         mappings.
@@ -513,9 +511,6 @@ def __init__(
         label_pairs : List[hashable], optional
             Pairs of labels merged during split correction. Default is an
             empty set.
-        use_segment_mapping : bool, optional
-            Indication of whether to build mapping between segment IDs and
-            labels. Default is False.
         """
         # Instance attributes
         self.labels = labels
@@ -599,7 +594,7 @@ def get(self, label):
         str
             Class ID corresponding to the label.
         """
-        return self.mapping.get(label, "0") if self.labels else str(label)
+        return self.mapping.get(label, "0")
 
     # --- Helpers ---
     def node_labels(self, graph):
@@ -628,7 +623,7 @@ class LazyMapping(dict):
     Dictionary-like mapping that lazily converts labels to segment IDs.
     """
 
-    def __missing__(self, label):
+    def get(self, label, default=None):
         """
         Gets the segment ID corresponding to the given label.
 
@@ -636,6 +631,8 @@ def __missing__(self, label):
         ----------
         label : hashable
             Label to be converted into a segment ID.
+        default : None, optional
+            Placeholder for built-in routine. Default is None.
 
         Returns
         -------
diff --git a/src/segmentation_skeleton_metrics/skeleton_metrics.py b/src/segmentation_skeleton_metrics/skeleton_metrics.py
index 4560890..666e6b6 100644
--- a/src/segmentation_skeleton_metrics/skeleton_metrics.py
+++ b/src/segmentation_skeleton_metrics/skeleton_metrics.py
@@ -562,7 +562,7 @@ def remove_repeat_merge_sites(self):
             rm_idxs = set()
             for i, site in enumerate(self.merge_sites):
                 if i not in rm_idxs:
-                    idxs = kdtree.query_ball_point(site["World"], 40)
+                    idxs = kdtree.query_ball_point(site["World"], 30)
                     idxs.remove(i)
                     rm_idxs |= set(idxs)