observer not working; unless root of nested property is touched

components.service-x-toggler.js

import Ember from 'ember';

export default Ember.Component.extend({
  myService: Ember.inject.service(),
  
  actions: {
    toggleX() {
      this.get('myService').toggleX();
    }
  }
});

components.toggle-observer.js

import Ember from 'ember';

export default Ember.Component.extend({
  myService: Ember.inject.service(),
  numberOfToggles: 0,
  
  xObserver: Ember.observer('myService.x', function(){
    this.incrementProperty('numberOfToggles');
  }),
  
  init() {
    this._super(...arguments);    
    // TODO: Observer not working without this ridicilous get; comment out it to get it working!
    // this.get('myService');
  }
});

controllers.application.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  myService: Ember.inject.service()
});

services.my-service.js

import Ember from 'ember';

export default Ember.Service.extend({
  x: false,
  
  toggleX() {
    this.toggleProperty('x');
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{service-x-toggler}}
<br>
{{outlet}}
<br>
{{toggle-observer}}
<br>
Value of my-service's x is: {{myService.x}}

templates.components.service-x-toggler.hbs

{{yield}}
<button {{action 'toggleX'}}>Toggle X</button>

templates.components.toggle-observer.hbs

{{yield}}
my-service's x is toggled {{numberOfToggles}} of times.

twiddle.json

{
  "version": "0.11.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "2.10.2",
    "ember-data": "2.11.0",
    "ember-template-compiler": "2.10.2",
    "ember-testing": "2.10.2"
  },
  "addons": {}
}