I cant' explain, I just tried out. So my answer ist: it won't compile. Because you do override the method of EEE but you don't implement the method of DDD. This will work:
No... I was wrong... doiIt is not == doIt ;-).
So, after a while, and another try I'd say: it doesn't matter. The method in EEE is implementing and extending. Because both d.doIt() and e.doIt() will execute the method in Test: