Hamish,
I think the weighting was designed so that if you change lines or casting styles you can adjust the bottom hand weighting to give a nicer feel. A bit like wrapping lead core around your spool to get the same effect.
Ryobi certainly did a double tip fly rod a good few years ago which was actually pretty good, if not rung intrestingly (almost looked like spinning rod guides.)
Looking through some of the salmon forums some very respected casters/fisherman have said they are by far the best rods they have used...pretty impressive.
Certainly there beachcaster hold most UK and some world casting records and there carp rods are renowned for being the most advanced available with some amazing blanks, all autoclaved to produce the best.
And they are British through and through..which is nice