code: private static WritingThread createWritingThread(final Collection<Writer>[][] matrix) {
  		Collection<Writer> writers = getAllWriters(matrix);
  		WritingThread thread = new WritingThread(writers);
  		thread.start();
  		return thread;
  	}
docs: Creates a writing thread for a matrix of writers.
  
  @param matrix
  All writers
  @return Initialized and running writhing thread