code: func (cn *connection) shouldRequestWithoutBias() bool {
  	if cn.t.requestStrategy != 2 {
  		return false
  	}
  	if len(cn.t.readers) == 0 {
  		return false
  	}
  	if len(cn.t.conns) == 1 {
  		return true
  	}
  	if cn == cn.t.fastestConn {
  		return true
  	}
  	return false
  }
docs: // The connection should download highest priority pieces first, without any
  // inclination toward avoiding wastage. Generally we might do this if there's
  // a single connection, or this is the fastest connection, and we have active
  // readers that signal an ordering preference. It's conceivable that the best
  // connection should do this, since it's least likely to waste our time if
  // assigned to the highest priority pieces, and assigning more than one this
  // role would cause significant wasted bandwidth.