docs(router): fix grammar typo in preloader section (#2700)

tweaks some other related language.

Author: wardbell

public/docs/ts/latest/guide/router.jade

@@ -2148,28 +2148,28 @@ h3#preloading <i>Pre-Loading</i>: background loading of feature areas
   * No pre-loading at all which is the default. Lazy loaded feature areas are still loaded on demand.
   * Pre-loading of all lazy loaded feature areas.
 
-  The *Router* also supports [custom preloading strategies](#custom-preloading) to give us control of what we want to pre-load.
+  The *Router* also supports [custom preloading strategies](#custom-preloading) for fine control over which modules to pre-load.
 
-  We'll update our *CrisisCenterModule* to be loaded lazily by default and use the `PreloadAllModules` strategy to eagerly
-  it up.
+  We'll update our *CrisisCenterModule* to be loaded lazily by default and use the `PreloadAllModules` strategy 
+  to load _all_ lazy loaded modules as soon as possible.
 
 <a id="preload-canload"></a>
 .l-sub-section
   :marked
-    The **PreloadAllModules** strategy does not eagerly load feature areas protected by the [Can Load](#can-load-guard) and this is by design.
-    The *CanLoad* guard protects against loading feature area assets until authorized to do so. If you want to eagerly load all modules and guard
-    them against unauthorized access, use the [CanActivate](#can-activate-guard) guard instead.
+    The **PreloadAllModules** strategy does not load feature areas protected by a [CanLoad](#can-load-guard) guard and this is by design.
+    The *CanLoad* guard blocks loading of feature module assets until authorized to do so. If you want to both preload a module and guard
+    against unauthorized access, use the [CanActivate](#can-activate-guard) guard instead.
 
 :marked
-  We'll update our route configuration to eagerly load the *CrisisCenterModule*. We follow the same process as we did when we loaded the *AdminModule* asynchronously.
+  We'll update our route configuration to lazy load the *CrisisCenterModule*. We follow the same process as we did when we loaded the *AdminModule* asynchronously.
   In the *crisis-center-routing.module.ts*, we'll change the *crisis-center* path to an *empty path* route.
 
   We'll move our redirect and *crisis-center* route to our `AppRoutingModule` routes and use the `loadChildren` string to load the *CrisisCenterModule*.
   The redirect is also changed to load the `/heroes` route on initial load.
 
   Once we're finished, we'll remove the `CrisisCenterModule` from our `AppModule`'s imports.
 
-  Here are our updated modules:
+  Here are the updated modules _before enabling preload_:
 
 +makeTabs(
    `router/ts/app/app.module.ts,
@@ -2183,9 +2183,10 @@ h3#preloading <i>Pre-Loading</i>: background loading of feature areas
   `)
 
 :marked
-  In order to enable pre-loading of all modules, we'll import the `PreloadAllModules` token from the router package. The second argument in the
-  `RouterModule.forRoot` method takes an object where we can provide additional configuration options. We'll use the `preloadingStrategy` property
-  with the `PreloadAllModules` token. This enables the built-in *Router* pre-loader to eagerly load **all** [unguarded](#preload-canload) feature areas that use `loadChildren`.
+  The second argument in the `RouterModule.forRoot` method takes an object for additional configuration options. 
+  We import the `PreloadAllModules` token from the router package and set the configuration option's `preloadingStrategy` property
+  with this `PreloadAllModules` token. 
+  This tells the built-in *Router* pre-loader to immediately load **all** [unguarded](#preload-canload) feature areas that use `loadChildren`.
 
 +makeExcerpt('app/app-routing.module.6.ts (preload all)', '')