I have a 900 credit rating and pay everything off in advance of the statements. We use credit cards for convenience and rebates, not because we need the credit. Admittedly it took more than a few years to get to that point.
No one said you needed credit. I simply said to let the statement show that the credit has been used.
For a score like that you must have a balance somewhere each month. Mortgage, car payments, line of credit, something because a credit card showing ZERO on every balance every month does not help a credit score at all and can be a detriment regardless of your score or position on the matter. And your score is great btw, but the best scores can be achieved by carrying a 4%-30% balance because it shows you can manage the debt. Also, diversifying your debt across different lending types play a large part as well.
I don't pay interest either, but I leave a little on for the reporting and then pay it off when I get the statement. I have tried the zero balance route and it does in fact lower the score over time. But if you have a large history the effect may not be noticeable to you.
EDIT: Also paying off my car early lowered my rating too because I no longer have an open Install plan type of credit. I'm just talking small amounts though like 10-20 points, not 100's.