I don't see this making much difference unless those 37% of crashes were done by drivers with a BAC between 0.05 and 0.08. My guess is that the alcohol related crashes were probably above anyway.

Sure it'll catch a few more in that interval after the crash has already happened or in random stops, but if they actually want to avoid the crashes they need other measures. Lower speed limits would help more, but I guess it's more important to focus on finding more people to blame than to avoid the crashes.

That's a really stupid way too say 63% of crashes did not involve alcohol. Why not focus on that number instead?