diff --git a/src/FlatArrayTrait.php b/src/FlatArrayTrait.php
index d3218f7..e985190 100644
--- a/src/FlatArrayTrait.php
+++ b/src/FlatArrayTrait.php
@@ -148,9 +148,7 @@ trait FlatArrayTrait
      */
     protected function flattenSearch(?string $name, $value = null, $unset = false)
     {
-        //normalize key names in $value, and also $name
-        $value = $this->normalizeValue($value);
-        $name = $name;
+
         //check for home strings
         if ($name == '' || $name === null) {
             if ($unset) {
@@ -201,20 +199,4 @@ trait FlatArrayTrait
         }
         return @$parent[$key];
     }
-
-    protected function normalizeValue($value)
-    {
-        if (!is_array($value)) {
-            return $value;
-        }
-        $norm = [];
-        foreach ($value as $key => $value) {
-            $nKey = preg_replace('/\./', '', $key);
-            if ($nKey == '') {
-                throw new \Exception("Key \"$key\" can't be used inside a FlatArray");
-            }
-            $norm[$nKey] = $this->normalizeValue($value);
-        }
-        return $norm;
-    }
 }
diff --git a/src/SelfReferencingFlatArray.php b/src/SelfReferencingFlatArray.php
index 9dbd206..be12251 100644
--- a/src/SelfReferencingFlatArray.php
+++ b/src/SelfReferencingFlatArray.php
@@ -1,9 +1,12 @@
 <?php
 /* Flatrr | https://gitlab.com/byjoby/flatrr | MIT License */
+
 namespace Flatrr;
 
 class SelfReferencingFlatArray extends FlatArray
 {
+    protected $cache = [];
+
     public function get(string $name = null, bool $raw = false, $unescape = true)
     {
         $out = parent::get($name);
@@ -19,12 +22,13 @@ class SelfReferencingFlatArray extends FlatArray
 
     public function set(?string $name, $value)
     {
-        return $this->filter(parent::set($name,$value));
+        $this->cache = [];
+        return $this->filter(parent::set($name, $value));
     }
 
     public function push(?string $name, $value)
     {
-        return $this->filter(parent::push($name,$value));
+        return $this->filter(parent::push($name, $value));
     }
 
     public function pop(?string $name)
@@ -34,7 +38,7 @@ class SelfReferencingFlatArray extends FlatArray
 
     public function unshift(?string $name, $value)
     {
-        return $this->filter(parent::unshift($name,$value));
+        return $this->filter(parent::unshift($name, $value));
     }
 
     public function shift(?string $name)
@@ -96,14 +100,15 @@ class SelfReferencingFlatArray extends FlatArray
         //search/replace on string values
         if (is_string($value) && strpos($value, '${') !== false) {
             //search for valid replacements
-            return preg_replace_callback(
-                //search for things like ${var/name}, escape with \ before last brace
-                '/\$\{([^\}]*[^\.\\\])\}/S',
-                //replace match with value from $this if it exists
-                [$this, 'filter_regex'],
-                //applied to $value
-                $value
-            );
+            return $this->cache[$value] ??
+                ($this->cache[$value] = preg_replace_callback(
+                    //search for things like ${var/name}, escape with \ before last brace
+                    '/\$\{([^\}]*[^\.\\\])\}/',
+                    //replace match with value from $this if it exists
+                    [$this, 'filter_regex'],
+                    //applied to $value
+                    $value
+                ));
         }
         //fall back to just returning value, it's some other datatype
         return $value;