Why to Use Explicit Interface Implementation To Invoke a Protected Method?

When browsing ASP.NET MVC source code in codeplex, I found it is common to have a class explicitly implementing interface. The explicitly implemented method/property then invoke another "protected virtual" method/property with same name.

For example,

public class MvcHandler : IHttpHandler, IRequiresSessionState 
{
    protected virtual bool IsReusable 
    {
        get 
        {
           return false;
        }
    }

    bool IHttpHandler.IsReusable 
    {
        get 
        {
           return IsReusable;
        }
    }
}

I'm now sure what's the benefit of this kind of programming. For me, I prefer to just implicitly implement the interface IHttpHandler.

I guess the author just don't want MvcHandler has a public property IsResuable. The property IsReusable can only be used when instance of MvcHandler is treated as a IHttpHandler. Still, I'm not sure why the author what this way.

Anybody know more benefits about this style of interface implementation?