Updated "from WPF" doc.

docs/tutorial/from-wpf.md

@@ -40,17 +40,6 @@ placed in a `DataTemplates` collection on each control (and on `Application`):
         <ContentControl Content="{Binding Foo}"/>
     <UserControl>    
 
-`ItemsControl`s don't currently have an `ItemTemplate` property: instead just
-place the template for your items into the control's `DataTemplates`, e.g.
-
-    <ListBox Items="ItemsSource">
-        <ListBox.DataTemplates>
-            <DataTemplate>
-                <TextBlock Text="{Binding Caption}"/>
-            </DataTemplate>
-        </ListBox.DataTemplates>
-    </ListBox>
-
 Data templates in Avalonia can also target interfaces and derived classes (which
 cannot be done in WPF) and so the order of `DataTemplate`s can be important:
 `DataTemplate`s  within the same collection are evaluated in declaration order
@@ -92,13 +81,8 @@ referred to using the `{StyleResource}` markup extension both inside and outside
 styles.
 
 For non-style-related resources, we suggest defining them in code and referring
-to them in markup using the `{Static}` markup extension. There are [various
-reasons](http://www.codemag.com/article/1501091) for this, but briefly:
-
-- Resources have to be parsed
-- The tree has to be traversed to find them
-- XAML doesn't handle immutable objects
-- XAML syntax can be long-winded compared to C#
+to them in markup using the `{Static}` markup extension. To read more about the reasoning for this,
+see [this issue comment](https://github.com/AvaloniaUI/Avalonia/issues/462#issuecomment-191849723).
 
 ## Grid