That makes sense. Granted even if they did language models, most spellers can only be used for short periods of time because of eye strain. Is that low hanging fruit or just small improvements on a still unviable approach? And if you're using motor imagery spellers...you're adding a model to like 2-4 bits of input. The efficiency there is horrible.

I'm with you on "I'd prefer an eye tracker." Modern advances in eye tracking (saccade-based stuff!) are pretty sick, and make the technology usable for long periods of time. You have higher bandwidth input than motor imagery, and don't torture the eye like P300.