We find that while optimizing its reformulations to adapt to the language of the QA system, AQA diverges from well structured language in favour of less fluent, but more effective, classic information retrieval (IR) query operations.  
 Question: What is the difference in findings of Buck et al? It looks like the same conclusion was mentioned in Buck et al..
AQA diverges from well structured language in favour of less fluent, but more effective, classic information retrieval (IR) query operations