Near-perfect infantry accuracy before Operation Dynamo

How would the Allies use infantry weapons with 99 percent accuracy three days before Operation Dynamo?

They would destroy German infantry, tanks, and low aircraft fast enough to hold the perimeter, although command problems would still slow a counterattack.

The scenario grants Allied infantry 99 percent accuracy with any visible target inside a weapon's maximum range from 23 May 1940, three days before the evacuation begins. Rifles and Bren guns would devastate exposed infantry and low aircraft, while Boys antitank rifles and precisely placed mortar bombs could disable tanks or strike fortifications. German formations would therefore suffer losses too quickly to force the Dunkirk perimeter into the sea. The panel still preserves an important caveat: Allied coordination and artillery problems do not vanish merely because infantry can hit. A successful counterattack may take time, but Operation Dynamo itself is likely to become unnecessary because the German advance stalls first.