I was taking a look at
Wicked 15 for the min-skills for max-% thread, and I have to call into question the 7-builder result for that level in this thread. The result is first mentioned in my post
here, but I made a reference to Proxima's earlier work, which I can't seem to find anywhere. I'm sure I took the 7-builder result from his original post, since I can't seem to replicate it myself.
Later on, Proxima posted this in a post that appears to have been deleted, but not before it was quoted by Clam:
Wicked 15 -- now that I'm actually playing this in Lemmix, it looks like my previous result may be incorrect. It seems that in the original game you have to place 6 bricks under the hatch to make the fall safe, and that can only be done using a clever trick seen in this video
This suggests that the 7-builder solution may have been incorrect. I'm going to assume it is unless someone can provide evidence confirming that it's doable. The fewest I was able to use, while still saving 48/50, is 9 builders.