In terms of Rudder Fences there is also the issue of what height they are at, as lower down the foil can generate downforce during a slight nosedive that could help keep the bow out.  I would agree that they should be either tightly defined, or outlawed.

It appears that according to the ERS defintion then a fence is illegal as it is part of an "hull appendage attached to a centreboard, daggerboard, bilgeboard
or rudder, primarily used to affect leeway and/or produce vertical lift."
what does a fence do?
They must be illegal, no?
I also found that the halyard bag / lunch bag has been through technical at the RYA and is illegal. maybe we could have a little addendum on the current rules? on this website and on the RYA site, its pretty hard to find the ruling from the RYA.
it is here for those like me that wondered: https://www.rya.org.uk/SiteCollectionDocuments/technical/Web%20Documents/CR%20interpretations/Merlin_Rocket_Class%20Rule_Interpretation_March_2018.pdf 

In relation to the OP, the comment regarding "insufficient to be passed" at the last MROA committee meeting I aske the associations Hon Secretary to look into how we might address this very issue, the Hon Secretary is due to report their initial ideas to committee in January 2020 so please be assured that this is being looked at.
 
Points 1 & 2 there is a great deal of work currently taking place around both of these issues behind the scenes, I would hope that both matters will be resolved before the start of the 2020 Silver Tiller series and considerably sooner if at all possible.
 
Point 3 I would not currently envisage this happening there are a large number of sail measurers around the country. 
 
I have added the RYA Technical Committee Rule interpretation to the Rules page it can be found by the following the rules tab from the "About" drop down menu on the home page.
 
 

Looking long term what's the point in being a measurer if IHC is going to do it all?
 
The course itself costs, then you have to be an RYA member to enable you to measure.
 
So my prediction would the that over time we would lose our class measurers and with them a whole raft of knowledge.
 
Then there is the independent verification side which in our class is rather important. I'm not referring to deliberate cheating, but in a restricted class such as ours with open class rules people like to push the limits. I think having a measurers ticket and signature on the sail carries rather more clout than an IHC ticket which is like saying "Well I think its ok". 
 
Of course sail measurers might get the odd decision wrong, but they cant be accused of not being impartial.
 
So I would advocate keeping away from IHC because in the bigger picture it will help the class and the sailmakers themselves.