从通用抽象类派生的类的C#方法重载问题

我在抽象类中定义的派生类中重载方法遇到了一个有趣的问题.这是一个代码示例：

public abstract class AbstractConverter<T,U>
    where U : AbstractConvertible
    where T : AbstractConverter<T,U>
{
    public abstract T Convert(U convertible);
}

public class DerivedConvertibleConverter : AbstractConverter<DerivedConvertibleConverter,DerivedConvertible>
{
    public DerivedConvertibleConverter(DerivedConvertible convertible)
    {
        Convert(convertible);
    }

    public override DerivedConvertibleConverter Convert(DerivedConvertible convertible)
    {
        //This will not be called
        System.Console.WriteLine("Called the most derived method");
        return this;
    }

    public DerivedConvertibleConverter Convert(Convertible convertible)
    {
        System.Console.WriteLine("Called the least derived method");
        return this;
    }
}

public abstract class AbstractConvertible {}

public class Convertible : AbstractConvertible {}

public class DerivedConvertible : Convertible {}

在上面的示例中,调用了抽象父级中不存在的Convert的重载(并且派生次数较少).我希望可以调用来自父类的派生程度最高的版本.

在尝试解决此问题时,我遇到了一个有趣的解决方案：

public abstract class AbstractConverter<U>
    where U : AbstractConvertible
{
    public abstract AbstractConverter<U> Convert(U convertible);
}

public class DerivedConvertibleConverter : AbstractConverter<DerivedConvertible>
{
    public DerivedConvertibleConverter(DerivedConvertible convertible)
    {
        Convert(convertible);
    }

    public override DerivedConvertibleConverter Convert(DerivedConvertible convertible)
    {
        System.Console.WriteLine("Called the most derived method");
        return this;
    }

    public DerivedConvertibleConverter Convert(Convertible convertible)
    {
        System.Console.WriteLine("Called the least derived method");
        return this;
    }
}

public abstract class AbstractConvertible {}

public class Convertible : AbstractConvertible {}

public class DerivedConvertible : Convertible {}

从基类中删除派生类型参数时,将调用转换的派生版本.我不希望这种差异,因为我不希望转换的抽象版本的接口发生变化.但是,我一定是错的.谁能解释为什么会出现这种差异？非常感谢你提前.