Fake.AllInstances<MyType>() not behaving as described

I was having some trouble using Fake.AllInstances<> so I began simplifying my code and it is now as simple as it can get and it still seems to be behaving differently from what I have seen described here in the answers to other questions.

My understanding is that when I call Isolate.Fake.AllInstances<TradeSummary>(), all existing and future instances of TradeSummary will be the same as the fake returned from this call.  Furthermore, I can use the returned fake to set up WhenCalled() to perform subsequent verification of method calls.

Here is my code:

			TradeSummary fakeTradeSummary = Isolate.Fake.AllInstances<TradeSummary>();
			Isolate.WhenCalled(() => fakeTradeSummary.Summarize(null)).CallOriginal();
			TradeSummary summ = new TradeSummary();
			summ.Summarize(new List<Trade>());
			Assert.AreSame(fakeTradeSummary, summ);
			Isolate.Verify.WasCalledWithAnyArguments(() => summ.Summarize(null));

TypeMock.TypeMockException : *** Isolate.Verify does not support objects that were not faked
 using Isolate.Fake.Instance(), or passed through WhenCalled()