This depends on which field of study you're in. If you want to go to grad school for astrophysics, getting that high GPA score is important. But, I do agree tha

This depends on which field of study you're in. If you want to go to grad school for astrophysics, getting that high GPA score is important. But, I do agree that halving your time to get a B+ versus an A is good. This type of decision making shows that you're good at managing your time and setting your priorities right.