Refresh Controller with navigationBar that has prefersLargeTitles set to true

I am using a navigation controller and within that navigation controller, I have a VC with a tableview that is hugging the top, bottom, left and right sides of the superView. When I have self.navigationController?.navigationBar.prefersLargeTitles set to false, everything works fine. But when I set it to true, I have to drag really really far down to get my refresh controller to trigger the refresh. I have to drag so far down that I have to use two fingers on the screen to drag down. Am I doing something wrong here or is this an issue with Apple? Here is how I am adding the refresh controller. I didn't include the handleRefresh function because the code doesn't even reach that point.

var refreshControl = UIRefreshControl()

override func viewDidLoad() {
    super.viewDidLoad()
    refreshControl.addTarget(self, action: 
    #selector(FeedViewController.handleRefresh(_:)), for: UIControlEvents.valueChanged)
    refreshControl.tintColor = UIColor.gray
    self.tableView.refreshControl = refreshControl
}

I am using swift 4 and iOS 11 with Xcode 9. The cells in my tableview are large - one cell is around 400-500 points so almost the size of the screen.

What happens is, the animator starts to animate but when it gets a certain (the point where it should refresh), it just stops. I have included a screenshot of the point at which it stops. Then when I keep on scrolling down further and further, it does the refresh. But it should have done it much earlier. I have to scroll down to the point where the nav bar stretches to almost the entire length of the screen.