thanks to all who replied
its encouraging to know that the RYA'S ethos of education not legislation is fimly in place with those who replied,
most if not all are advanced powerboaters with dayskipper theory
some very well qualified safe powerboaters are out there.
with regard to the theory for the dayskipper, yes it is biased towards sailing how ever the theory is the same for both,better to do the course through a powerboat/motor cruising school as they will throw in the extras for powerboaters eg 6 min rule for high speed