One thing that puzzles me about the "new" theories about elites coming over and conquoring the islands and converting the language is that:

1) Why did not the celtic languages die out after the Roman invasion?
2) Why did the celtic (or latin) die out when the Angles/Saxons/Jutes arrived (whom I'm sure did not speak the same language?
3) Why did English survive the Norman invasion (with many Latin and French loan words)?

What was so different or special about the Angles/Saxons/Jutes that wiped out 99.9% of the indigenous language? A feat totally beyond the Norman ruling elite.