Clarify comment

Remove an ambiguous part of the comment that can cause confusion -
passing a WaitGroup by pointer is always mandatory.

examples/waitgroups/waitgroups.go

@@ -23,8 +23,6 @@ func main() {
 	// This WaitGroup is used to wait for all the
 	// goroutines launched here to finish. Note: if a WaitGroup is
 	// explicitly passed into functions, it should be done *by pointer*.
-	// This would be important if, for example, our worker had to launch
-	// additional goroutines.
 	var wg sync.WaitGroup
 
 	// Launch several goroutines and increment the WaitGroup

examples/waitgroups/waitgroups.hash

@@ -1,2 +1,2 @@
-58031ceb701a1cab27498efd89adadbf1ea6b3e6
-vmjCBfN6MJE
+66d1c1cdb7e60f63b9b30938aa9c63b2262463ac
+S98GjeaGBX0

public/waitgroups

@@ -42,7 +42,7 @@ use a <em>wait group</em>.</p>
             
           </td>
           <td class="code leading">
-            <a href="http://play.golang.org/p/vmjCBfN6MJE"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
+            <a href="http://play.golang.org/p/S98GjeaGBX0"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
           <pre class="chroma"><span class="kn">package</span> <span class="nx">main</span>
 </pre>
           </td>
@@ -107,9 +107,7 @@ use a <em>wait group</em>.</p>
           <td class="docs">
             <p>This WaitGroup is used to wait for all the
 goroutines launched here to finish. Note: if a WaitGroup is
-explicitly passed into functions, it should be done <em>by pointer</em>.
-This would be important if, for example, our worker had to launch
-additional goroutines.</p>
+explicitly passed into functions, it should be done <em>by pointer</em>.</p>
 
           </td>
           <td class="code leading">