But as a hard and fast rule, it is too easy to get around.

This 10 percent share isn't a hard and fast rule, it's just a way to think about things.

So there is no hard and fast rules as to how much you need to pay.

There are no hard and fast rules on this sort of thing.

There are no hard and fast rules in this business.

It is a guide to action, rather than hard and fast rules.

"We are not quite ready to make any hard and fast rules."

Still, small sample size, so there are no hard and fast rules.

As it turns out, there are simply no hard and fast rules.

But others say that is no longer a hard and fast rule.