My question on this topic is how RRS 45 and RRS 48.2 interact in the situation described. 

According to RRS 48.2,

This means that intentionally leaving the boat is prohibited unless one of these specific exceptions applies.

RRS 45 states:

This allows the crew to stand on the bottom once they are already in the water, but it does not itself permit leaving the boat.

In my view, these two rules must be read together:
Standing on the bottom is allowed under RRS 45, but only if the crew is already in the water for a permitted reason under RRS 48.2.

Therefore, intentionally leaving the boat with the purpose of standing on the bottom to hold or stabilize the boat is prohibited under RRS 48.2, even though RRS 45 allows standing on the bottom.

In my opinion, the only situation in which holding the boat while standing on the bottom is allowed is when the crew has left the boat unintentionally, for example due to an accident such as a capsize. In such a case, the crew did not violate RRS 48.2, and RRS 45 permits them to stand on the bottom while recovering the boat. 

For the situation described at the starting line, the crew member left the boat intentionally to fix the boat’s position. This is not an emergency, nor an accidental departure, nor swimming. Therefore, even though RRS 45 allows standing on the bottom, the action is not permitted because the way the crew entered the water violates RRS 48.2. 

Niko: I like your "the RC should always work to have an appropriate level of management commensurate with the competition level/importance" comment.

There is one event that may partner and I run every year ... the Warneet Around French Island race. While Monica runs the briefing giving numerous examples of the flags used during the start sequence there is usually an America's Cup skipper sitting quietly and respectfully at the back of the room with his family or mates. At the other end of the spectrum we have some who have NEVER raced before or perhaps doing their second race since last year.

During this race I tend to be very chatty on the radio to be sure that even those with the least experience have a great day on the water.

One boat in his first year actually missed the starting line, but we considered him a starter. The next year his missed the finishing line but we gave him a finish regardless. He was so pleased that he got the start right the second year ;-)

That said, it is quite a different matter if I am running a one-design race.

I fully endorse John Standley's summary.
And I add this:
Neither boat was required to act to avoid contact until it became clear that the other was not keeping clear.
There was no action that W could have taken in time before L's contact.
And L undoubtedly began trimming her main back in before contact occurred as fast as possible.
Hence, neither boat violated RRS 14.

Jim Champ Reply to: 22039 - John Quirk: furthermore, in CASE 50, in the first sentence, it actually uses the term "genuine and reasonable apprehension" (this of course a standard used by courts with applications for an arrest in connection with non-bailable offences), and in the second sentence 'reasonable doubt' (again, a well-tested legal / court term). Quite some complexity for a competitor and PC to become acquainted with :).

And I appreciate it.

I never called you a blockhead.