diff --git a/src/calng/corrections/PnccdCorrection.py b/src/calng/corrections/PnccdCorrection.py
index 20d2e6885effe9b18604e897a3230f187f80b541..a4d8dfab6650d2eab4ec1ed7ac75e5fadce449a8 100644
--- a/src/calng/corrections/PnccdCorrection.py
+++ b/src/calng/corrections/PnccdCorrection.py
@@ -252,7 +252,6 @@ class PnccdCpuRunner(base_kernel_runner.BaseKernelRunner):
         cm_min_frac,
         cm_row,
         cm_col,
-        cm_block,
     ):
         output = self._q_processed_data[q]
         output[:] = self._q_input_data[q].astype(np.float32)
@@ -260,17 +259,11 @@ class PnccdCpuRunner(base_kernel_runner.BaseKernelRunner):
             output -= self._q_offset_map[q]
 
         if flags & CorrectionFlags.COMMONMODE:
-            # per rectangular block that looks like something is going on
             masked = np.ma.masked_array(
                 data=output,
                 mask=(self._q_bad_pixel_map[q] != 0)
                 | (output > self._q_noise_map[q] * cm_noise_sigma),
             )
-            if cm_block:
-                for block in np.hsplit(masked, 4):
-                    if block.count() < block.size * cm_min_frac:
-                        continue
-                    block.data[:] -= np.ma.median(block)
 
             if cm_row:
                 subset_rows = masked.count(axis=1) >= masked.shape[1] * cm_min_frac
@@ -296,7 +289,6 @@ class PnccdCpuRunner(base_kernel_runner.BaseKernelRunner):
         cm_min_frac=0.25,
         cm_row=True,
         cm_col=True,
-        cm_block=True,
     ):
         # NOTE: how to best clean up all these duplicated parameters?
         for result in self.thread_pool.map(
@@ -308,7 +300,6 @@ class PnccdCpuRunner(base_kernel_runner.BaseKernelRunner):
                 cm_min_frac=cm_min_frac,
                 cm_row=cm_row,
                 cm_col=cm_col,
-                cm_block=cm_block,
             ),
             range(4),
         ):
@@ -406,20 +397,12 @@ class PnccdCorrection(base_correction.BaseCorrection):
             .defaultValue(True)
             .reconfigurable()
             .commit(),
-
-            BOOL_ELEMENT(expected)
-            .key("corrections.commonMode.enableBlock")
-            .assignmentOptional()
-            .defaultValue(True)
-            .reconfigurable()
-            .commit(),
         )
         PnccdCorrection._managed_keys |= {
             "corrections.commonMode.noiseSigma",
             "corrections.commonMode.minFrac",
             "corrections.commonMode.enableRow",
             "corrections.commonMode.enableCol",
-            "corrections.commonMode.enableBlock",
         }
         PnccdCalcatFriend.add_schema(expected, PnccdCorrection._managed_keys)
         # TODO: bad pixel node?
@@ -459,7 +442,6 @@ class PnccdCorrection(base_correction.BaseCorrection):
             cm_min_frac=self.unsafe_get("corrections.commonMode.minFrac"),
             cm_row=self.unsafe_get("corrections.commonMode.enableRow"),
             cm_col=self.unsafe_get("corrections.commonMode.enableCol"),
-            cm_block=self.unsafe_get("corrections.commonMode.enableBlock"),
         )
         self.kernel_runner.correct(
             flags=self._correction_flag_enabled, **args_which_should_be_cached