title: Product with Serializable - reason for
body: <p>The following: </p>
  
  <pre><code>import scala.collection.mutable.ListBuffer
  val saveLineValues1 = ListBuffer(("Apple", "Banana"), ("Orange", "Pineapple", "Kiwifruit"))
  </code></pre>
  
  <p>shows:</p>
  
  <pre><code>saveLineValues1: scala.collection.mutable.ListBuffer[Product with Serializable] = ListBuffer((Apple,Banana), (Orange,Pineapple,Kiwifruit))
  </code></pre>
  
  <p>What impact does it have on processing? Cannot see any reasonable explanation for this. I understand the SO 37477709 thread, but not so here. Beacuse I did not state a class? I think a lot of people are using SCALA without understanding some aspects, like this.</p>