Palgia
What is needed here is a deeper understanding of the mechanism of colour vision.
Colour vision is different for everybody. The supposed Gold standard for measuring red green discriminatory ability is the Nagel anomaloscope.
when a large group of colour normals are tested on the nagel anomaloscope each one will have a slightly different result. The anomaloscope is not per se a test it is a diagnostic tool the matching range is decided by statistical treatment of the results gathered from the "Normal" group anyone who falls within this number of standard deviations is considered normal and anyone who falls outside of this is considered abnormal the anomaloscope can actually tell you what you are seeing by giving you a red green ratio and from that you can approximate what percentage of green or red you are seeing relative to the normal sample.
All colour tests including the anomaloscope are prone to errors and misdiagnosis. In the FAA studies that you quoted they identified miss and false alarm rates for each test. The rates varied between the studies so reaching a conclusion about what they mean is difficult however one particular conclusion that can be reached is that somewhere in the order of 1 out of every 100 people who pass the ishihara test are unable to tell the difference between aviation signal lights (red green and white). This is surprising because the ishihara is thought to be 'bullet proof' by the JAA medical committee however it lets about 1% pass who should not.
There is conclusive evidence that the signal light test as administered by the FAA is a very good predictor of colour percetion. It has a 100% safety record stretching back to the days before the FAA even existed. According to the NTSB they are unaware of any accident where a colour deficient pilot flying without restrictions by virtue of the signal light test has every had an incident or accident where a causal or additional factor has been the pilot mistaking a safety critical colour.
When you consider the numbers (current estimates put the number of such pilots in the US in the order of 10000) the complete absence of accidents is very telling indeed.
There is circumstantial evidence that having a colour standard at all is redundant, however there is no hard evidence. Dr Pape in Australia is the expert on this. If true and it probably is it would explain why the colour deficient community is so damn safe.
In one of your posts you speak of common sense, I ask you when did the JAA ever give us any indication of having anything resembling common sense? Don't credit them with something that they don't have.