High-speed blending can indeed generate heat in water due to molecular friction, although the effect may be minimal. Stirring water with a spoon already produces slight warming, indicating that any mechanical work done by blender blades could transfer some heat. The blades are designed to slice through the water, resulting in lower force on the water compared to paddles, which would be more effective for heating. Theoretical calculations suggest that the heat generated depends on the work done by the blades, defined as force times distance. Overall, while blending may warm the water slightly, it may not be significant without a different blade design.