You aren't following the methods 110% if you are working during lunch. But lets think about this... say you work 1.5 hrs a week unpaid during lunch....
I will use $50/hr b/c most likely you are working over 8 every day. (this is rounding down and assuming we never get another raise)
50/hr (OT pay) x 1.5 = $75 a week
$75x48 weeks = $3,600 yr
Now think if you took that $3,600 a year you are GIVING AWAY, and paid it towards your mortgage, car, or college savings etc.
OR lets say you have a newborn at home, that you want to see 20 mins earlier, and you took that $3,600/yr and saved it for 18 years until college.
Without and interest that would be $64,800.
With 5% interest, over 18 years that 15-20 mins a day is worth $106,000!!!!!
Is it REALLY that important to sort off the clock???