Singleton потокобезопасная реализация без lock

using System;
using System.Threading;
using System.Linq;

class Program
{
   static void Main(string[] args)
   {
        (new Thread(()=>
        {
             var sing = Singleton.GetInstance();
             Console.WriteLine(sing.Date);
        })).Start();

        var sing2 = Singleton.GetInstance();
        Console.WriteLine(sing2.Date);

        Console.ReadLine();
   }
}

class Singleton
{
    private static readonly Singleton instance = new Singleton();

    public string Date{get; private set;}

    private Singleton()
    {
        this.Date = DateTime.Now.TimeOfDay.ToString();
    }

    public static Singleton GetInstance()
    {
        return instance;
    }
}