Actually, in a different world (Norway, actually), the tax people are obliged by law to calculate your tax in the way which result in the lowest tax for the taxpayer (based on the numbers they have been given, of course). That of course include all deductions you are entitled to. No tricks.
Also, most institutions deliver the numbers in electronic format to the tax office so that we get a filled in form with the numbers and an estimated tax which we can use as a starting point for the tax return. For a fair number of taxpayers the pre-filled in form contain the correct numbers.