Convert Property Change to Observable

INPC enable binding V <-> VM and need ICommand to execute request to Server side. It is interesting to see if Observables in Rx running on
a TaskPoolScheduler can do the same as Delagete or Relay Command. Both FromEventPattern and CLR event should work

    public class ViewModel : INotifyPropertyChanged
    {
        public string Cusip { get; set; }
        public double Ask { get;set; }

        public event PropertyChangedEventHandler PropertyChanged;

        public IObservable<Tuple<T, string>> OnSubmitChanges<T>(Expression<Func<ViewModel, T>> exp)
        {
            MemberExpression me = exp.Body as MemberExpression;
            string n = me.Member.Name;
            Func<ViewModel, T> f = exp.Compile();
            T i = f.Invoke(this);
            return Observable.Return(new Tuple<T,string>(i,n));
        }

        public ViewModel()
        {
            PropertyChanged += ViewModel_PropertyChanged;
//  Observable.FromEventPattern<PropertyChangedEventHandler, PropertyChangedEventArgs>(hh => hh.Invoke, h => this.PropertyChanged += h, h => this.PropertyChanged -= h)
                .Subscribe((e) => { ViewModel_PropertyChanged(this, e.EventArgs); });
        }

        private void ViewModel_PropertyChanged(object sender, PropertyChangedEventArgs e)
        {
// From Event Pattern does not need subscribe again. Direct call Server side is enougth.
            if (e.PropertyName == "Cusip")
                OnSubmitChanges(vm => vm.Cusip).Subscribe((i) => { Console.WriteLine("Call IVMController->IModObsAdapter->IModObsTransport->QueueAsObserver " + i); }); //459200-10-1 //912828NB2
            if (e.PropertyName == "Ask")
                OnSubmitChanges(vm => vm.Ask).Subscribe((i) => { Console.WriteLine("Hit bid lift offer " + i); });

        }
    }


        private static void TestConvertPropChangeToObservable()
        {
            ViewModel v = new ViewModel();
            v.Cusip = "912828NB2";
            v.OnSubmitChanges(vm => vm.Cusip).Subscribe((i) => { Console.WriteLine("Call IVMController->IModObsAdapter->IModObsTransport->QueueAsObserver " + i); }); //459200-10-1 //912828NB2
            v.Ask = 98.23;
            v.OnSubmitChanges(vm => vm.Ask).Subscribe((i) => { Console.WriteLine("Hit bid lift offer " + i); }); 

        }