A task input is received at a well service rig. The maximum allowable speed is determined for the task. Current block speed inputs are received. The throttle position for the engine controlling the block is evaluated to determine if the block is to be sped up or slowed down. When the throttle position indicates the operator is attempting to speed up the block, the current block speed is compared to the maximum allowable speed and the engine is only allowed to speed up the block up to the maximum allowable speed, at which point the operators control of block speed is limited to reducing block speed. Each task can have multiple maximum allowable speeds, which can vary based on specified conditions. When the hookload is light or the remaining equipment in the well is small, the lock-up feature for the transmission can be disengaged in addition to the block speed governing feature.