Personally, I think it must be not only timeboxed, but also targeted. This targeting can be done by writing down what exactly are you supposed to discover, and what exactly should you deliver (knowledge, prototype, etc.) by the end of the timebox.
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Personally, I think it must be not only timeboxed, but also targeted. This targeting can be done by writing down what exactly are you supposed to discover, and what exactly should you deliver (knowledge, prototype, etc.) by the end of the timebox.