I disagree with their conclusion, because if you changed the question to say “the structure must be at least 3 Lego blocks high” without telling people to subtr

I disagree with their conclusion, because if you changed the question to say “the structure must be at least 3 Lego blocks high” without telling people to subtract blocks then I think it would probably solicit similar results. Their conclusion is that people will add rather than take away, so you should tell people to take away. My conclusion is that people will add rather than take away if not provided enough information about the problem space. I think the solution is to better define the problem, otherwise you can come up with lots of proposals that aren’t suitable. If I don’t know if making the guy lie down is allowed I’m going to have to make an assumption and either under-optimise or over-optimise. My view is saying you can remove bricks implies that roof height isn’t important, which changes the users assumption on requirements. The learning should be more clarity on requirements, rather than just “ask people to reduce rather than increase”. Additionally, if you changed the rule and said “participants will be scored based on the number of blocks removed”, I assume you would also get people creating silly scenarios like the ones I described and wholly unsuitable designs. This is more realistic in the real world where less material = less cost.