I think the better approach would be to "risk rate" your SARS and close the accounts where you feel the risk of illegal or fraudulent activity is high enough to harm the bank.
Hence a risk based approach. Imagine that

All joking aside, PR said it perfectly. There is a big difference between SAR filings.
Customer A is running a legitimate business, paying his taxes, has good balances and a loan relationship, is doing everything right, except for structuring his deposits because his CPA told him about the big, bad bank reporting all customers who deposit or withdrawal more than $10M in cash.
Customer B is a convenience store who offers money transmission services, isn't registered with FinCEN, is depositing more cash than can be expected given his size and location and refuses to return calls when asked to provide more information.
You cannot tell me that the risk level for both customers is the same and both accounts warrant closure. To steal a line from a frequent poster on these very boards, ask your self these two questions: Is the relationship profitable? Is their legitimate risk presented by maintaining the relationship?