diff --git a/src/Grafoscopio/GrafoscopioNode.class.st b/src/Grafoscopio/GrafoscopioNode.class.st
index ffd97af..cf9b4c2 100644
--- a/src/Grafoscopio/GrafoscopioNode.class.st
+++ b/src/Grafoscopio/GrafoscopioNode.class.st
@@ -42,8 +42,8 @@ GrafoscopioNode class >> cleanTreeRootReferences [
 	clipboard preorderTraversal allButFirstDo: [ :n |
 			ref := n.
 			n level - 1 timesRepeat: [ ref := ref parent ].
-			ref ifNotNil: [ ref parent: nil ] 
-	] 
+			ref parent = clipboard parent ifTrue: [ ref parent: nil ]].
+	clipboard parent: nil.
 ]
 
 { #category : #accessing }
diff --git a/src/Grafoscopio/GrafoscopioNotebook.class.st b/src/Grafoscopio/GrafoscopioNotebook.class.st
index 86ba225..d279f12 100644
--- a/src/Grafoscopio/GrafoscopioNotebook.class.st
+++ b/src/Grafoscopio/GrafoscopioNotebook.class.st
@@ -127,8 +127,8 @@ GrafoscopioNotebook >> exportAsMarkdown [
 	workingFile 
 		ifNil: [ self inform: 'File NOT exported. Please save the notebook on hard drive first' ]
 		ifNotNil: [
+			self markdownFile exists ifTrue: [ self markdownFile delete ].
 			self markdownFile 
-				exists ifTrue: [ self markdownFile delete ];
 				ensureCreateFile;
 				writeStreamDo: [:stream | stream nextPutAll: self notebook asMarkdown].
 			self inform: ('File exported as: ', String cr, self markdownFile fullName)]
diff --git a/src/Grafoscopio/ManifestGrafoscopio.class.st b/src/Grafoscopio/ManifestGrafoscopio.class.st
index c02cdad..30f813f 100644
--- a/src/Grafoscopio/ManifestGrafoscopio.class.st
+++ b/src/Grafoscopio/ManifestGrafoscopio.class.st
@@ -12,6 +12,11 @@ ManifestGrafoscopio class >> ruleRBAssignmentInIfTrueRuleV1FalsePositive [
 	^ #(#(#(#RGMethodDefinition #(#GrafoscopioNode #embedNodes #false)) #'2017-02-16T20:07:02.600781-05:00') )
 ]
 
+{ #category : #'code-critics' }
+ManifestGrafoscopio class >> ruleRBBooleanPrecedenceRuleV1FalsePositive [
+	^ #(#(#(#RGMethodDefinition #(#'GrafoscopioNode class' #cleanTreeRootReferences #true)) #'2017-03-27T22:18:17.447627-05:00') )
+]
+
 { #category : #'code-critics' }
 ManifestGrafoscopio class >> ruleRBClassNameInSelectorRuleV1FalsePositive [
 	^ #(#(#(#RGMethodDefinition #(#'Documentation class' #current #true)) #'2016-10-07T19:39:23.013722-05:00') )