How strictly do you follow the 70 percent rule?

[Brendan Chism]

Whenever you are first getting into real estate investing, you are hammered with the 70 percent rule when evaluating what is a good deal or not. It is kinda of made out to be if a deal doesn't fix this rule then it is not a deal, however, how strictly do people interpret this rule when there is still a lot profit to be made on a deal but doesn't exactly fit the 70 percent rule?