TT automatically chooses the higher of itemized deductions or the standard deduction (if you enter your itemized deduction info otherwise the standard deduction will be used) you can override this choice to use the standard deduction even if less than itemized. you'll probably end up paying more in income taxes if you make this choice.
for married filing separate they both must use the same method. but TT goes through a series of questions to determine which should be used.
