I have new appreciation for the Sistine Chapel. All the planks are official, OSHA-stamped scaffolding planks, but they are a little bouncy. I did put one up on short blocks and bounce up and down on it before I trusted them in place.
The best thing is it signifies near completion. Setting up the scaffolding is time consuming. And in addition to the ceiling there is painting, and the window trim. I estimate completion early next year.