So they got the figures for HS 1 terribly, terribly wrong:
International passenger numbers on HS1 are a third of the original 1995 forecast and two-thirds of the DfT's 1998 forecast, it stated.
BBC News - HS1 Channel link leaves £4.8bn debt, says MPs
Will they do better with HS 2 and what about forecasts for airline pax growth...?
By the way, the above £4.8bn is going to be picked up by the UK tax payer. Also, don't forget that the combined British/French company that built the Chunnel had to be saved from bankruptcy.
Now, back to talking of that shiny new slab of infrastructure in the middle of the river ...