2/2 Hands-free or speed-free on the roads plus awesome site visit (part 2) as HS2 again under scrutiny

Is Christian Wolmar's sceptical view of self-driving vehicles vindicated by the report from the House of Commons Transport Committee [1:59]?  Does the new default 20mph speed limit on residential streets in Wales point the way to better road safety or economic ruin [9:50]?  Will political choices leave the breathtaking HS2 Old Oak Common station as the terminus of a bizarre Acton to Aston railway [15:37}?  Christian and co-presenter Mark Walker set out to answer these questions.