SSAT scores as a method of BS selection

How much is SSAT score REALLY linked to how intelligent someone is though? I think there is some correlation, and it kind of puts everyone on one level to compare, but I go to a school/background where standardized testing is not felt to be that accurate. Also, as my dad says, there are skills…like being able to BS your way through things and being able to read a teacher and figure out what makes them tick that are more linked to actual success in school and life vs JUST ability to perform on one test (he says he had to study a lot less in school - he was smart yes, but he understood exactly what he needed to do to be successful at certain things and was able to spend less time on some things and not on others). I kind of get that even though I am just in middle school.