diff --git a/gtsam/linear/SimpleSPCGSolver.cpp b/gtsam/linear/SimpleSPCGSolver.cpp
index 4379d70e4..e7cef9e64 100644
--- a/gtsam/linear/SimpleSPCGSolver.cpp
+++ b/gtsam/linear/SimpleSPCGSolver.cpp
@@ -49,7 +49,8 @@ SimpleSPCGSolver::SimpleSPCGSolver(const GaussianFactorGraph &gfg, const Paramet
 
   nVar_ = colSpec.size();
 
-  /* split the factor graph into At (tree) and Ac (constraints) */
+  /* Split the factor graph into At (tree) and Ac (constraints)
+   * Note: This part has to be refined for your graph/application */
   GaussianFactorGraph::shared_ptr At;
   boost::tie(At, Ac_) = this->splitGraph(gfg);
 
diff --git a/gtsam/linear/SimpleSPCGSolver.h b/gtsam/linear/SimpleSPCGSolver.h
index 416826cc7..c7367f663 100644
--- a/gtsam/linear/SimpleSPCGSolver.h
+++ b/gtsam/linear/SimpleSPCGSolver.h
@@ -78,7 +78,8 @@ protected:
   /* return x = Rt^{-1} y + x_t */
   VectorValues::shared_ptr transform(const VectorValues &y);
 
-  /* naively split a gaussian factor graph into tree and constraint parts */
+  /* naively split a gaussian factor graph into tree and constraint parts
+   * Note: This function has to be refined for your graph/application */
   boost::tuple<GaussianFactorGraph::shared_ptr, FactorGraph<JacobianFactor>::shared_ptr>
   splitGraph(const GaussianFactorGraph &gfg);