Ken,
that was exactly my argument as to why we needed to carry them. If you could ,in extremis, ditch then you had the comfort of two MS26 liferafts to climb in to. Why would you want to jump into the water otherwise ?
In the early days of the RAF C130 tanker we were driven by the 'Marham Mafia' in respect of operating our tanker. This is why we carried parachutes (the Victor had them) and the HDU panel was fitted above the Nav station. The 'spare' Nav in the Victor operated the panel which ideally should have been affixed to the forward face of the HDU frame.There were other irritations.
Remember this is the same school of thought that had an escape exit cut into the VC10 tankers on the port side of the fuselage.