18. The computer readable storage device of claim 17 , wherein the computer-executable instructions are further executable by the computer for: determining that each additional utterance decoder of the plurality of utterance decoders is unlikely to be capable of accurately decoding the spoken utterance; and terminating decoding of the spoken utterance.
19. The computer readable storage device of claim 18 , wherein the accuracy of the decoded spoken utterance is determined based on confidence values returned by the first utterance decoder in the series and the second utterance decoder in the series.