transferring unused tuition amount

I have read that I should not transfer my kid's unused tuition amount to myself unless I am using it to reduce my tax payable to Zero.  Without using the tuition amount, I will actually be getting a refund.  If I add in the tuition amounts both federal and provincial, my refund increases.  Why then does the Turbotax information say not to transfer the unused tuition amount unless I am reducing my tax payable to zero. It appears to be beneficial if I do.  I am in New Brunswick