There are many reasons to cold move as opposed to hot moving. One of them is availability of a command qualified officer and a CERA on board, other ones are time and available personnel considerations. There is also the fact, Colin, that in the RCN, unlike the Coast Guard, we have our own tugs present in harbour and dedicated to nothing else than service of the fleet. Unlike the CCG, we don't have to hire outside tug companies. Finally, our hulls are generally not of the type you can bounce into things, again unlike yours, and it comes down to "why take chances with a billion dollars asset if you can avoid problems by spending a few thousand dollars", especially for the subs and frigates.