Non-violent resistance was a good strategy, evidenced by sit-ins in Nashville, Tennessee in 1960. Businesses lost money, and they eventually gave in to integration. Nashville eventually became the first major southern city to integrate its public systems on May 10, 1960. This shows that non-violent resistance was effective.
Non-violent resistance was an ineffective strategy, as demonstrated during Freedom Summer in 1964. It was an attempt to help black voters in Mississippi, but instead there were widespread beatings, shootings, and bombings, most of which went largely unpunished. Therefore, non-violent resistance was not a good strategy.