"was based"
you've answered your own question, charlie
the RNLI don't design well.
they have always had designers such as Watson do them, but when it comes to in house, they perfectly well stuff up a design by changing it.
the last boat before the FAB's which include the Waveney was the Clyde.
this was orriginally a flat transome designed boat, but the RNLIgot hold of it, changed it to what it became, and the designer of the Clyde never designed for them again.
they can't leave well enough aloan, sadly, and always want change, whether it is to the detriment of the original concept or not.
as you say, the EFFSEEBEE IS based on another boat, but what they ended up with was a million miles away from that original design, so i have been told.
i mean, you only have to look at the new Tamar class, and the design problems and the mechanics of getting it all to work properly to see what i mean.
the launching and recovery process of the Y boat from the opening transom stern is a health and safety nightmare in it's own right.
don't get me wrong though. I AM NOT KNOCKING THE BRAVERY AND STANDING of any lifeboat crewman or woman.
I have probably more respect for them than any person on this site, having had my life saved by them 51 years ago this june.
I just find that in any organisation there are those at the top who will not listen to the shop floor operative.
And in this case it's the crew men ,who have to operate the boats, and as such gave the big thumbs down to the FCB,in some cases stating that they thought the RNLI development was in some cases, dangerous in certain sea conditions,
Sadly often crew members opinions are not taken into accountand the management think they know better because they have those magic letters after their names.