title: Linking multiple TransformBlocks to single BatchBlock TPL
body: <p>I've built two pipelines using <code>TPL Dataflow</code>:</p>
  
  <pre><code>TransformBlock =&gt; TransformBlock =&gt; BatchBlock =&gt; ....
  
  TransformBlock =&gt; BatchBlock =&gt; TransformBlock =&gt; ....
  </code></pre>
  
  <p>I want to accomplish</p>
  
  <pre><code>            / =&gt; Transform Block =&gt; TransformBlock =&gt; BatchBlock =&gt; ....
  BatchBlock /
             \
              \ =&gt; Transform Block =&gt; BatchBlock =&gt; TransformBlock =&gt; ....
  </code></pre>
  
  <p>However only the first pipeline gets executed.</p>
  
  <p>My code</p>
  
  <pre><code>batchMediaBlock.LinkTo(pipelineA.FirstBlock, new DataflowLinkOptions {PropagateCompletion = true});
  batchMediaBlock.LinkTo(pipelineB.FirstBlock, new DataflowLinkOptions {PropagateCompletion = true});
  </code></pre>
  
  <p>How can I accomplish this?</p>