diff --git a/lib/mixins/element-mixin.html b/lib/mixins/element-mixin.html
index 92b728d714..a3bb9c9eec 100644
--- a/lib/mixins/element-mixin.html
+++ b/lib/mixins/element-mixin.html
@@ -124,8 +124,6 @@
 
     let caseMap = Polymer.CaseMap;
 
-    const DISABLED = 'disable-upgrade';
-
     /**
      * Returns the `properties` object specifically on `klass`. Use for:
      * (1) super chain mixes togther to make `propertiesForClass` which is
@@ -453,8 +451,6 @@
       proto._bindTemplate(template);
     }
 
-    function flushPropertiesStub() {}
-
     /**
      * @polymerMixinClass
      * @unrestricted
@@ -472,7 +468,7 @@
        */
       static get observedAttributes() {
         if (!this.hasOwnProperty(JSCompiler_renameProperty('__observedAttributes', this))) {
-          let list = [DISABLED];
+          let list = [];
           let properties = propertiesForClass(this);
           for (let prop in properties) {
             list.push(Polymer.CaseMap.camelToDashCase(prop));
@@ -720,19 +716,7 @@
        * @override
        */
       attributeChangedCallback(name, old, value) {
-        // process `disable-upgrade` specially:
-        // First we see `disable-upgrade` added and disable `_flushProperties`,
-        // then when it's removed, restore regular flushing and flush.
-        // This should only be allowed before "readying".
-        if (name === DISABLED && !this.__dataInitialized) {
-          if (value !== null) {
-            this.__flushProperties = this._flushProperties;
-            this._flushProperties = flushPropertiesStub;
-          } else {
-            this._flushProperties = this.__flushProperties;
-            this._flushProperties();
-          }
-        } else if (old !== value) {
+        if (old !== value) {
           let property = caseMap.dashToCamelCase(name);
           let type = propertiesForClass(this.constructor)[property].type;
           if (!this._hasReadOnlyEffect(property)) {
diff --git a/lib/mixins/template-stamp.html b/lib/mixins/template-stamp.html
index af17ee3bfe..1a26c7937e 100644
--- a/lib/mixins/template-stamp.html
+++ b/lib/mixins/template-stamp.html
@@ -118,11 +118,6 @@
      */
     class TemplateStamp extends superClass {
 
-      _initializeProperties() {
-        super._initializeProperties();
-        this.$ = null;
-      }
-
       /**
        * Scans a template to produce template metadata.
        *
diff --git a/test/runner.html b/test/runner.html
index e15a8de0a5..8df2426d90 100644
--- a/test/runner.html
+++ b/test/runner.html
@@ -71,8 +71,7 @@
       'unit/logging.html',
       'unit/mixin-utils.html',
       'unit/mixin-behaviors.html',
-      'unit/render-status.html',
-      'unit/disable-upgrade.html'
+      'unit/render-status.html'
     ];
 
     // http://eddmann.com/posts/cartesian-product-in-javascript/
diff --git a/test/smoke/disable-upgrade.html b/test/smoke/disable-upgrade.html
deleted file mode 100644
index 0897b46d03..0000000000
--- a/test/smoke/disable-upgrade.html
+++ /dev/null
@@ -1,98 +0,0 @@
- <!--
-@license
-Copyright (c) 2017 The Polymer Project Authors. All rights reserved.
-This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
-The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
-The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
-Code distributed by Google as part of the polymer project is also
-subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
--->
-<!DOCTYPE html>
-<html>
-<head>
-  <script src="../../../webcomponentsjs/webcomponents-lite.js"></script>
-  <link rel="import" href="../../polymer.html">
-</head>
-<body>
-
-<dom-module id="x-child">
-  <template>
-    <style>
-      :host {
-        display: block;
-        border: 2px solid lightgreen;
-        margin: 2px;
-        padding: 2px;
-      };
-    </style>
-    <div>I'm a child, yo!</div>
-  </template>
-  <script>
-    HTMLImports.whenReady(function() {
-      class XChild extends Polymer.Element {
-        static get is() { return 'x-child'}
-        static get properties() {
-          return {
-            prop: { value: 'hi'}
-          }
-        }
-      }
-      customElements.define(XChild.is, XChild);
-    });
-  </script>
-</dom-module>
-
-
-<dom-module id="x-test">
-  <template>
-    <style>
-      :host {
-        display: block;
-        border: 2px solid orange;
-        padding: 2px;
-      };
-    </style>
-    <div>element says: {{prop}}</div>
-    <x-child id="child" disable-upgrade$="[[disabled]]"></x-child>
-  </template>
-  <script>
-    HTMLImports.whenReady(function() {
-      class XTest extends Polymer.Element {
-        static get is() { return 'x-test'}
-        static get properties() {
-          return {
-            prop: { value: 'hi'},
-            disabled: {value: true}
-          }
-        }
-
-        ready() {
-          super.ready();
-          setTimeout(() => {
-            // this.$.child.removeAttribute('disable-upgrade');
-            this.disabled = false;
-          }, 1000)
-        }
-      }
-      customElements.define(XTest.is, XTest);
-    });
-  </script>
-</dom-module>
-
-
-<h2>Enabled</h2>
-<x-test></x-test>
-<x-test></x-test>
-<h2>Disabled</h2>
-<script>
-  function go() {
-    Array.from(document.querySelectorAll('[disable-upgrade]'))
-      .forEach((e) => e.removeAttribute('disable-upgrade'));
-  }
-</script>
-<button onclick="go()">Go</button>
-<x-test id="one" disable-upgrade></x-test>
-<x-test id="two" disable-upgrade></x-test>
-
-</body>
-</html>
diff --git a/test/unit/disable-upgrade.html b/test/unit/disable-upgrade.html
deleted file mode 100644
index c90387fe95..0000000000
--- a/test/unit/disable-upgrade.html
+++ /dev/null
@@ -1,158 +0,0 @@
-<!doctype html>
-<!--
-@license
-Copyright (c) 2017 The Polymer Project Authors. All rights reserved.
-This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
-The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
-The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
-Code distributed by Google as part of the polymer project is also
-subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
--->
-<meta charset="utf-8">
-<script src="../../../webcomponentsjs/webcomponents-lite.js"></script>
-<script src="../../../web-component-tester/browser.js"></script>
-<link rel="import" href="../../polymer.html">
-
-<dom-module id="x-lazy">
-  <template>
-    <style>
-    :host {
-      display: block;
-    }
-    </style>
-    <div id="child">Live!</div>
-  </template>
-  <script>
-  HTMLImports.whenReady(function() {
-    Polymer({
-      is: 'x-lazy'
-    });
-  });
-  </script>
-</dom-module>
-
-<test-fixture id="simple">
-  <template>
-    <x-lazy disable-upgrade></x-lazy>
-  </template>
-</test-fixture>
-
-<dom-module id="x-complicated-child">
-  <script>
-  HTMLImports.whenReady(function() {
-    Polymer({
-      is: 'x-complicated-child',
-      properties: {
-        a: {
-          observer: 'aChanged'
-        },
-        c: {
-          observer: 'cChanged'
-        },
-        aRan: {
-          value: false
-        },
-        cRan: {
-          value: false
-        }
-      },
-      aChanged: function() {
-        this.aRan = true;
-      },
-      cChanged: function() {
-        this.cRan = true;
-      }
-    });
-  })
-  </script>
-</dom-module>
-
-<dom-module id="x-complicated-lazy">
-  <template>
-    <x-complicated-child id="child" a="{{a}}" disable-upgrade$="{{b}}" c="{{c}}"></x-complicated-child>
-  </template>
-  <script>
-  HTMLImports.whenReady(function() {
-    Polymer({
-      is: 'x-complicated-lazy',
-      properties: {
-        a: {value: true},
-        b: {value: true},
-        c: {value: true}
-      }
-    });
-  });
-  </script>
-</dom-module>
-
-<test-fixture id="databind-lazy">
-  <template>
-    <x-complicated-lazy></x-complicated-lazy>
-  </template>
-</test-fixture>
-
-<dom-module id="x-complicated-not-lazy">
-  <template>
-    <!-- the <x-non-lazy> element here ensures there are other elements on -->
-    <!-- the host-stack to trigger "configuration", to ensure the disabled -->
-    <!-- element handles that code path correctly -->
-    <x-non-lazy></x-non-lazy>
-    <x-complicated-child id="child" a="{{a}}" disable-upgrade$="{{b}}" c="{{c}}"></x-complicated-child>
-  </template>
-  <script>
-  HTMLImports.whenReady(function() {
-    Polymer({
-      is: 'x-non-lazy'
-    });
-    Polymer({
-      is: 'x-complicated-not-lazy',
-      properties: {
-        a: {value: true},
-        b: {value: false},
-        c: {value: true}
-      }
-    });
-  });
-  </script>
-</dom-module>
-
-<test-fixture id="databind-not-lazy">
-  <template>
-    <x-complicated-not-lazy></x-complicated-not-lazy>
-  </template>
-</test-fixture>
-
-<script>
-suite('Element disableUpgrade', function() {
-  suite('disable-upgrade', function() {
-    var el;
-    setup(function() {
-      el = fixture('simple');
-    });
-    test('does not stamp when lazy', function() {
-      assert.equal(el.hasAttribute('disable-upgrade'), true);
-      assert.notOk(el.shadowRoot);
-      assert.notOk(el.$);
-    });
-    test('stamps when disableUpgrade is removed', function() {
-      el.removeAttribute('disable-upgrade');
-      assert.ok(el.root);
-      assert.ok(el.$.child);
-    });
-  });
-  suite('disableUpgrade and Databinding', function() {
-    test('binding to disable-upgrade with true', function() {
-      var el = fixture('databind-lazy');
-      assert.equal(el.$.child.hasAttribute('disable-upgrade'), true);
-      assert.equal(el.$.child.aRan, false);
-      assert.equal(el.$.child.cRan, false);
-    });
-    test('bindings to disable-upgrade with false', function () {
-      var el = fixture('databind-not-lazy');
-      assert.notOk(el.$.child.hasAttribute('disable-upgrade'));
-      assert.equal(el.$.child.aRan, true);
-      assert.equal(el.$.child.cRan, true);
-    })
-  })
-});
-</script>
\ No newline at end of file
