The Importance of Stress Tests in Banking

I thought we learned from the 2008 crisis about the importance of stress tests or was that just a Canadian thing? I mean really if what this ends up doing is causing banks to actually tighten the credit that they're offering inside of the marketplace more than is appropriate. If financial institutions get to the point where they say well look we have to tighten liquidity more than we were going to then the probability of an economy slowing down more than otherwise would have been the case is definitely now on the table.