It would be interesting to know whether there's really a tendency for gifted children to go from nothing to real talking (one would have to define carefully what one meant!) faster than the average, separately from the question of when they start. Anecdotally it looks to me as though that might be the case, but it's hard to tell - it may be just that the process of learning to speak generally seems astonishingly fast to adults! It was certainly our experience: DS went from 5 individual words to 5-word sentences in 4 months, but he wasn't quite putting two words together when he turned 2, IIRR.
