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GitHub User: martinrehfeld
What's with Authlogic anyhow? I always felt it was the better level of abstraction compared to Devise.
I've been exercising a similar practice manually for a while now and I can confirm it really makes controllers more concise and readable in 99% of the cases. Good to know it has been wrapped up as a Gem now.
Instead of changing Rails' JSON default (or mapping to the attributes as shown), you could also check out the jsonContainer option of the Tokeninput plugin.