diff --git a/include/ck_tile/ops/reduce/block/block_reduce2d.hpp b/include/ck_tile/ops/reduce/block/block_reduce2d.hpp
index 5715d82390..beb8c718e3 100644
--- a/include/ck_tile/ops/reduce/block/block_reduce2d.hpp
+++ b/include/ck_tile/ops/reduce/block/block_reduce2d.hpp
@@ -218,8 +218,6 @@ struct BlockReduce2dCrossWarpSync
         if constexpr(num_reduce_warps == 1)
             return;
 
-        // CAUSION - Imitate BlockWelfordCrossWarpSync, but looks like there are some bugs.
-
         // store into smem only for lane-0 within one warp
         if(lane_id == 0)
         {
@@ -237,22 +235,18 @@ struct BlockReduce2dCrossWarpSync
             static_for<0, num_reduce_warps, 1>{}([&](auto i_1) {
                 all_scratch[i_0 * num_reduce_warps + i_1] =
                     smem_ptr[i_0 * num_warps + local_smem_os + i_1];
-                // all_scratch[i_0 * num_warps + i_1] =
-                //     smem_ptr[i_0 * num_reduce_warps + local_smem_os + i_1];
             });
         });
         block_sync_lds(); // TODO: we don't need sync here
 
         static_for<0, thread_buf_size, 1>{}([&](auto i_0) {
             // TODO: use descriptor for this
-            // auto v_local = all_scratch[i_0 * num_warps];
             auto v_local = all_scratch[i_0 * num_reduce_warps];
 
             // further reduce mean/var
             static_for<0, num_reduce_warps - 1, 1>{}([&](auto i_1_n1) {
                 constexpr auto i_1      = number<i_1_n1 + 1>{};
                 const DataType v_remote = all_scratch[i_0 * num_reduce_warps + i_1];
-                // const DataType v_remote = all_scratch[i_0 * num_warps + i_1];
 
                 // reduce
                 v_local = reduce_func(v_local, v_remote);