Yes, it would. Under FATCA, the financial institution is charged with the obligation. It is required to agree to collecting this information. If it doesn't collect it, then one of the penalties that can be imposed—or the incentives, if you can put it that way—on the client to make them compliant with the financial institution's request is account closure, in addition to or in opposition to, as an alternative to withholding.
The IGA takes that away. It's all about account reporting. If the client comes up with only so much information and no more, then the financial institution provides to the CRA what it has, and that's what goes to the U.S. The U.S. can make further inquiries through the CRA under our exchange of information procedures in that event.