[sushiburps]

I was with BofA during this time, around 2006. On top of posting highest to lowest, they had a hidden account allowance, called a "Matrix allowance", which was basically a hidden line of credit behind every checking account. It was the maximum amount of money the bank would allow the account to become overdrawn before denying transactions. The allowance amount increased if the account became overdrawn frequency and the overdraft fees were paid.