your last point is spot-on; I have a decent yamaha electric piano and the action is quite a bit heavier than my sister's Boston acuostic. It's not suprising but

your last point is spot-on; I have a decent yamaha electric piano and the action is quite a bit heavier than my sister's Boston acuostic. It's not suprising but still notable how much more fatigued you feel after an hour of playing mine vs. hers.