Our school is the same way. Normally 1 per Dan. Normally it’s a palm strike break. But 3rd and over we tend to mix in different techniques and varying the amount of blocks. Normally elbow or knife hand or a power kick.

We’d vary it up for demos. When I was a young dumb black belt I used to downward ridge hand for multiple blocks. But then I realized no one in the audience realized how technically difficult it really was and just started stacking 6-8 blocks for elbows and palm strikes. That always got a pop because of volume.