The implied consent is before the actual arrest....although it (via testing) may lead to the arrest.
It seems your issue is with implied consent then and not the actual arrest correct? I cannot follow the line of though wrt unsolved DUI as related to I/C you mentioned so pls clarify that or dismiss it and advise of your true issue.
An arrest for DUI carries a stigma regardless of conviction and refusing a breath test results in loss of license in most states; therefor, all arrests should be made on the basis of observed impairment while driving (checkpoints bypass this) rather than the stock, "bloodshot eyes, unsteady on feet, strong smell of alcohol..." that has become a litany in hearings.
No other crime has such a conviction record as DUI.
If the goal is to end driving with any alcohol present in the driver's system, the honest thing to do would be to lobby for that, not simply broaden the target zone.
My major gripe lies with the roadblock tactic, not the goal of stopping impaired drivers.