CBT-I can be effective depending on what the underlying cause of the insomnia is. There are many causes ranging from excessive worry and rumination such as one would find in anxiety and depression; mania may bring about changes in circadian and social rhythms. Food, stimulants or alcohol may be causes of insomnia as can poor sleep hygiene or environmental issues.
While CBT or CBT-I may be part of the treatment plan for each of these situations, the nature of the targets and the particular methods may change, depending on what the treater discovers as the underlying cause of the insomnia.
With regard to the American Academy of Sleep Medicine, please see their treatment guidelines. Here is a citation and a URL to retrieve them.
Sharon Schutte-Rodin, M.D.; Lauren Broch, Ph.D. ; Daniel Buysse, M.D. ; Cynthia Dorsey, Ph.D.; Michael Sateia, M. (2008). Clinical Guideline for the Evaluation and Management of Chronic Insomnia in Adults. Journal of Clinical Sleep Medicine, Vol. 4, No. 5, 487-504.
Sleep Medicine Reviews has a nice review on time in bed restriction. I think it is "in press" at the moment, but it is available online. Miller et al. (2014)
As for cognitive therapy (CBT-I minus time in bed restriction), there is some research supporting its use, but the effects are not as great as when behavioral methods are blended in. See Harvey et al. (2014) for a recent paper on this topic. They found that cognitive therapy takes a while to get going, but still provides good results.