A strike needn't be long to be effective. Timed and executed right, a strike can be won in minutes. Such strikes are "sitdowns" when everyone just stops work and sits tight, or "mass grievances" when everybody leaves work to go to the boss' office to discuss some matter of importance.
The Detroit (USA) I.W.W. employed the Sitdown to good effect at the Hudson Motor Car Company between 1932 and 1934. "Sit down and watch your pay go up" was the message that rolled down the assembly line on strickers that had been fastened to pieces of work. The steady practice of the sitdown raised wages 100% (from $.75 an hour to $1.50) in the middle of a depression.
I.W.W. theater extras, facing a 50% pay cut, waited for the right time to strike. The play had 150 extras dressed as Roman soldiers to carry the Queen on and off the stage. When the cue for the Queen's entrance came, the extras surrounded the Queen and refused to budge until the pay was not only restored, but tripled.
Sitdown occupations are still powerful weapons. In 1980, the KKR Corporation announced that it was going to close its Houdaille plant in Ontario and move it to South Carolina. The workers responded by occupying the plant for two weeks. KKR was forced to negotiate fair terms for the plant closing, including full pensions, severance pay, and payment towards health insurance premiums.