"passive" exercising, does it truly burn/

I started a tae kwon do class a few weeks ago. Tonight we worked on our forms. I was a sweaty mess by the end but didnt' truly feel the same sort of accomplishment I do with repetitive, focused exercising. The exercise log for tae kwon do shows 800 cal burn for a full hour. I know the calorie expenditures for exercising are estimates only, and I know in this art movements can vary greatly. My awesome black belt boyfriend told me to think about how my body was in constant controlled motion, which is true. Do I need to rethink my idea of calorie burn? Could controlled passive movements of all my muscle groups truly burn anywhere close to this many calories in an hour? I usually only count 30 minutes because I know there are moments we stand listening for instruction, but still.