There is space for both sorts of tests - in the same way that there is space for both with and without calculator maths examinations.
They are testing two different things, one is testing your recall of the basic foundations of the subject, which you shouldn't need reference material for - the other is your ability to understand the topic, know it well enough to get to the correct place in the reference material and put forward a reasoned argument for something much deeper than could be achieved in a closed book exam.
In terms of the calculator I very rarely type anything into a calculator without having done the mental arithmetic to know what sort of number I am expecting to see come out (order of magnitude, approximate value of first digit, should it be rational...). And that's a key skill, for which explicit mental arithmetic training and testing should be encouraged.
Biting the hand that feeds IT
