OK, cool. What about adding hooks to already-instantiated objects? This is the behaviour I've currently got:

```
    TestWithCustomForwardInvocation *testClass = [TestWithCustomForwardInvocation new];

    id token = [TestWithCustomForwardInvocation aspect_hookSelector:@selector(test) withOptions:AspectPositionInstead usingBlock:^(__unsafe_unretained id object, NSArray *arguments) {
        // Custom hook
    } error:NULL];

    [testClass test]; // doesn't call custom hook
```

I personally see that as acceptable, but it's up to you.