SIR – I have working in construction and engineering all my life, and fail to see how the HS2 project can cost so much and take so long to complete. In France, there is a high-speed link from Rennes to Paris that was first discussed in 2005, tendered in 2008, commenced construction in 2012 and opened in 2017. The new line is a twin track, 113 miles long and cost in the region of 2.5 billion euros. That included the upgrade of a further 20 miles of tack, purchase of land and all the infrastructure required to do so. Not only that, but the line cuts a small channel through the country side. I appreciate we need to have substantial tunnelling for HS2, but I would ask who is responsible for the cost control and why has no value engineering taken place....