Within the abstract:
> The average accuracy and information transfer rate are 92.25% and 37.62 bits per minute, which is translated in the speller with an average speed of 5.51 letters per minute.
5.51 letters per minute, not words. The work you cited is not comparable to the UCSF work at all.
It seems you are measuring performance in terms of bit-rate (i.e. based on how many symbols per minute), which makes sense when you are using a cursor-based speller.
This approach is not a correct measurement of bitrate with this speech-motor decoder, however, as words are being decoded based on the syllables contained within it. The decoding model is trained to recognize 50 specific combinations of syllables, and the total number of unique single syllable phonemes is about 44.