The result of attempting to whip cream in a blender is a thick, velvety substance rather than fluffy whipped cream  This is because a blender' s container does not let in enough air to whip cream effectively
Although using a special whipping-cream attachment in a blender can help somewhat, it cannot fully compensate for the container' s poor air intake
When attempting to whip cream in a blender, using a special whipping-cream attachment always produces a fluffier result than could be obtained without using such an attachment.