If you are exceptionally strong in some area, you're probably exceptionally weak in another area.
That might be true sometimes, but sure not always.
I know e.g. a guy that scores good grades at an elite university, has a good social life (and a girlfriend), is a pretty good musician that plays the violin in a university orchestra and actually is really good at a lot of sports, too.
On the other hand there are people that aren't exceptionally strong in any area but still are exceptionally weak in others.
IQ tests are pressure tests and have no real bearing on the ability of a person to function properly in life any less than another.
That is not true.
There are certain university subjects where it is necessary to pass some sort of IQ-test to attend; BECAUSE they DO mean something (even if it's just the correlation between the grades you'll achieve and the score you get).