diff --git a/dune/tectonic/myblockproblem.hh b/dune/tectonic/myblockproblem.hh
index e5e7508830094484fb4f78fa43712f89f61fe901..f226fd70a8eaecaa6b3e0672cc44a4ace1b69d3f 100644
--- a/dune/tectonic/myblockproblem.hh
+++ b/dune/tectonic/myblockproblem.hh
@@ -60,8 +60,14 @@ template <class MyConvexProblemTypeTEMPLATE> class MyBlockProblem {
   }
 
   std::string getOutput(bool header = false) const {
-    // TODO: implement (not urgent)
-    return std::string();
+    if (header) {
+      outStream.str("");
+      for (int j = 0; j < block_size; ++j)
+        outStream << "  trunc" << std::setw(2) << j;
+    }
+    std::string s = outStream.str();
+    outStream.str("");
+    return s;
   }
 
   void projectCoarseCorrection(VectorType const &u,
@@ -186,8 +192,8 @@ template <class MyConvexProblemTypeTEMPLATE> class MyBlockProblem {
           linearization.b[row][j] = 0.0;
     }
 
-    // for(int j=0; j<block_size; ++j)
-    //   outStream << std::setw(9) << linearization.truncation.countmasked(j);
+    for (int j = 0; j < block_size; ++j)
+      outStream << std::setw(9) << linearization.truncation.countmasked(j);
   }
 
   /** \brief Constructs and returns an iterate object */
@@ -203,6 +209,8 @@ template <class MyConvexProblemTypeTEMPLATE> class MyBlockProblem {
   Bisection bisection;
 
   Dune::ParameterTree const &parset;
+
+  mutable std::ostringstream outStream;
 };
 
 /** \brief Solves one local system using a scalar Gauss-Seidel method */