I may have jumped to the conclusion without proper diagnosis, but you got to understand my background: I got no help from doctors back then. Some advised me to go to a support group, some performed neurological tests on me, others made me do tests like listening comprehension, pattern recognition or some other kinds of tests of person's ability. Some people just listened to me and said I don't sound like a person with brain injury. One doctor doubted the validity of intelligence measures beyond 2 deviations above average and noted that all available data on the merits of high intelligence is based on tests which measure no more than 2 deviations above average. Comparing the results to those from general population, the doctors found nothing wrong and offered no kind of brain imaging tests or other forms of diagnosis which would have produced hard evidence. Neither would the offer any help, apart from meetings in a support group.
One test I had to perform as part of the hiring process showed I'm comparatively more prone to distraction in work compared to other professionals, my work is relatively free of error, but I work more slowly. This test was adjusted for professionals in jobs requiring the highest cognitive ability of any population, not the general population. In any case, comparisons with the general population was all that the doctors ever did.
As for math, I had pretty much the same experience you did. One time in high school I skipped most of the math lessons and all the exercises entirely for 2 months and the grade dropped. I learned I have to put something in for something to come out, so I resumed putting few hours a work per month to continue getting the top grades. In university, I had pretty easy time getting good grades now that I knew I had to work for them.
I would welcome a +20 IQ boost if one were available. The professional work setting is pretty hard, the demands to continuously educate myself is pretty taxing and I'd like it to become easier. The success is just low to moderate and I'd rather have the learning part become easy rather than hard. When I push my limits I'd rather win a competition than to place in the middle.
I think the early IQ results were just about as reliable as possible. The test makers had extrapolated the IQ score range based on a best fit between observations from test group and a parametric curve, and they had a peer-reviewed analysis of their method along with reliability and accuracy estimations, showing the test was good. Extending the range of IQ tests above norm + 2 deviations was supposedly pretty new back then.
Some research has been made on topic of intelligence since then. IQ above standard + 2 deviations doesn't much matter in most occupations. It's supposedly a non-issue. The intelligence distribution doesn't follow the standard deviation, either. There are more people in the +3, +4 and +5 range than predicted according to the standard distribution. The over-representation can get higher than 10 times the predicted number in the extremely high range. The expected number of people alive with high enough IQ is below 0.5 persons for this planet and it's population, so in all probability, no such people should be around. Instead we have 2 to 3 tested individuals and some others might go untested. Someone had to test them and convince others the results should be believed, and they did.
The post is way past TL;DR so I'll just cut it here!
I trust the validity of at least one the pre-NDE IQ tests and at least one of the post-NDE test. In lack of help from the doctors, I've made my own hypothesis. I don't spend time entertaining hypothesis, though, but I'm trying to arrange my work settings and habits the best I can to get the best of what I have now.
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