@@ -124,6 +124,14 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 {
 	// secretions and uptakes. Syncing with BioFVM is automated. 
 
+	static double time_since_last_phenotype = phenotype_dt_;
+	static double time_since_last_mechanics = mechanics_dt_;
+	static double phenotype_threshold = phenotype_dt_ - 0.5 * diffusion_dt_;
+	static double mechanics_threshold = mechanics_dt_ - 0.5 * diffusion_dt_;
+
+	bool time_for_phenotype = time_since_last_phenotype > phenotype_threshold;
+	bool time_for_mechanics = time_since_last_mechanics > mechanics_threshold;
+
 	#pragma omp parallel for 
 	for( int i=0; i < (*all_cells).size(); i++ )
 	{
@@ -132,36 +140,20 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 			(*all_cells)[i]->phenotype.secretion.advance( (*all_cells)[i], (*all_cells)[i]->phenotype , diffusion_dt_ );
 		}
 	}
-	
-	//if it is the time for running cell cycle, do it!
-	double time_since_last_cycle= t- last_cell_cycle_time;
-
-	static double phenotype_dt_tolerance = 0.001 * phenotype_dt_; 
-	static double mechanics_dt_tolerance = 0.001 * mechanics_dt_; 
 
 	// intracellular update. called for every diffusion_dt, but actually depends on the intracellular_dt of each cell (as it can be noisy)
-	if (initialzed)
-	{ update_all_cells_intracellular(); }
+	update_all_cells_intracellular();
 
-	if( time_since_last_cycle > phenotype_dt_ - 0.5 * diffusion_dt_ || !initialzed )
+	if( time_for_phenotype )
 	{
-		// Reset the max_radius in each voxel. It will be filled in set_total_volume
-		// It might be better if we calculate it before mechanics each time 
-		// std::fill(max_cell_interactive_distance_in_voxel.begin(), max_cell_interactive_distance_in_voxel.end(), 0.0);
-		
-		if(!initialzed)
-		{
-			time_since_last_cycle = phenotype_dt_;
-		}
-		
 		// new as of 1.2.1 -- bundles cell phenotype parameter update, volume update, geometry update, 
 		// checking for death, and advancing the cell cycle. Not motility, though. (that's in mechanics)
 		#pragma omp parallel for 
 		for( int i=0; i < (*all_cells).size(); i++ )
 		{
 			if( (*all_cells)[i]->is_out_of_domain == false )
 			{
-				(*all_cells)[i]->advance_bundled_phenotype_functions( time_since_last_cycle ); 
+				(*all_cells)[i]->advance_bundled_phenotype_functions( time_since_last_phenotype ); 
 			}
 		}
 
@@ -179,19 +171,13 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 
 		cells_ready_to_die.clear();
 		cells_ready_to_divide.clear();
-		last_cell_cycle_time= t;
+		time_since_last_phenotype = 0.0; // reset and then increment below for next cycle
 	}
+
+	time_since_last_phenotype += diffusion_dt_;
 
-	double time_since_last_mechanics= t- last_mechanics_time;
-	
-	// if( time_since_last_mechanics>= mechanics_dt || !initialzed)
-	if( time_since_last_mechanics > mechanics_dt_ - 0.5 * diffusion_dt_ || !initialzed )
+	if( time_for_mechanics )
 	{
-		if(!initialzed)
-		{
-			time_since_last_mechanics = mechanics_dt_;
-		}
-		
 		// new February 2018 
 		// if we need gradients, compute them
 		if( default_microenvironment_options.calculate_gradients ) 
@@ -248,7 +234,6 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 					for( int j=0; j < pC->state.spring_attachments.size(); j++ )
 					{
 						Cell* pC1 = pC->state.spring_attachments[j]; 
-						// standard_elastic_contact_function_confluent_rest_length(pC,pC->phenotype,pC1,pC1->phenotype,time_since_last_mechanics);  
 						standard_elastic_contact_function(pC,pC->phenotype,pC1,pC1->phenotype,time_since_last_mechanics);  
 					}
 				}
@@ -264,15 +249,9 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 			standard_cell_cell_interactions(pC,pC->phenotype,time_since_last_mechanics); 
 		}
 		// super-critical to performance! clear the "dummy" cells from phagocytosis / fusion
-		// otherwise, comptuational cost increases at polynomial rate VERY fast, as O(10,000) 
 		// dummy cells of size zero are left ot interact mechanically, etc. 
 		if( cells_ready_to_die.size() > 0 )
 		{
-			/*
-			std::cout << "\tClearing dummy cells from phagocytosis and fusion events ... " << std::endl; 
-			std::cout << "\t\tClearing " << cells_ready_to_die.size() << " cells ... " << std::endl; 
-			// there might be a lot of "dummy" cells ready for removal. Let's do it. 		
-			*/
 			for( int i=0; i < cells_ready_to_die.size(); i++ )
 			{ cells_ready_to_die[i]->die(); }
 			cells_ready_to_die.clear();
@@ -289,16 +268,18 @@ void Cell_Container::update_all_cells(double t, double phenotype_dt_ , double me
 			{ pC->update_position(time_since_last_mechanics); }
 		}
 
-		// When somebody reviews this code, let's add proper braces for clarity!!! 
-		
 		// Update cell indices in the container
 		for( int i=0; i < (*all_cells).size(); i++ )
-			if(!(*all_cells)[i]->is_out_of_domain && (*all_cells)[i]->is_movable)
-				(*all_cells)[i]->update_voxel_in_container();
-		last_mechanics_time=t;
+		{
+			if (!(*all_cells)[i]->is_out_of_domain && (*all_cells)[i]->is_movable)
+			{ (*all_cells)[i]->update_voxel_in_container(); }
+		}
+		time_since_last_mechanics = 0.0; // reset and then increment below for next cycle
 	}
-	
-	initialzed=true;
+
+	time_since_last_mechanics += diffusion_dt_;
+
+
 	return;
 }
 
 
@@ -84,7 +84,6 @@ class Cell_Container : public BioFVM::Agent_Container
 	std::vector<Cell*> cells_ready_to_divide; // the index of agents ready to divide
 	std::vector<Cell*> cells_ready_to_die;
 	int boundary_condition_for_pushed_out_agents; 	// what to do with pushed out cells
-	bool initialzed = false;
 
  public:
 	BioFVM::Cartesian_Mesh underlying_mesh;