Deductions & credits

I did say yes to that question. I do see where the math takes place but not clear why. On line 29 of the Car and Truck Worksheet it shows expenses of $15,242 and it subtracts $8,043 on line 30 (business portion of lease) leaving a total vehicle expense of $7199 on line 32 which would lead me to believe that I am not getting credit for lease payments. However, to test that I reduced the amount of the lease payments in the program and my amount of tax due went up! If I raise the amount of the lease payments, the tax due falls. How can a higher lease payment lower my total vehicle expense and tax bill at the same time? Just seems counterintuitive. Seems that a higher lease payment entry should raise my overall vehicle expense and lower my tax bill. I need a drink!