Mea culpa Simon: the Flight Global article was written to reflect the emergence of the security video rather than to analyse the accident. The low-end 100kt figure, derived in a few minutes, was based on very basic assumptions, and only intended to give a sense of proportion. Having since had the time for a more thorough assessment - from which we've also come up with a speed of 120-130kt - I'll be updating the figure in the story.
Ultimately the question isn't whether the A320 was travelling too fast - the overrun itself settles that - but rather why. Either it was decelerating normally but late, or it couldn't decelerate, or it was deliberately not decelerating.