I have carbon checks, solves the memory problem.
Could I tell you my balance if I didn't look at it for a couple days, yes, I could and be close enough. I don't check my account every day. I know what is in there and what we've spent and can give you a round number figure of what is in the account at every given time. I probably don't know the figure to the penny but we keep extra money in our account and we have automatic overdraft protection if needed. In this day and age there simply isn't a NEED to sit down with your statements monthly and balance your account if you have online access. I haven't "balanced" our checking account in over 10 years" and haven't ever had an issue. I can't remember the last time a charge showed up wrong on our account either.
No, there is no NEED to sit down and balance my checking account, but I still do it. For some reason, I enjoy doing it.