Earlier this week I spent the day with Rachel Hall from the Guardian down at the RNLI's Sea Survival training centre in Poole. The training centre is a standard 25 meter swimming pool which can be transformed into a stormy seascape complete with wind, rain and darkness at the pressing of a few buttons. The journalists in the dinghy were being given an experience of what it is like for migrants attempting the perilous crossing of the English Channel in unseaworthy boats.