Good post. It's nice to hear feedback. I was an organizer of some previous Bubble Cups (but I wasn't really involved in this one) and other competitions, so here's my view on the two points: 1. Test cases should be good. They should be designed so that weak solutions do not pass. Everyone should agree on this. On the other hand, I understand this task is not typical. I personally enjoy those kind of tasks. They require relying on some intuition and they are different than the standard 'identify the type of problem and apply some modification of the known idea to solve it' tasks. Yes, having a lot of experience and knowledge may be a disadvantage here actually, because you are less inclined to 'think outside of the box' of standard programming contest tasks. But you come up with these kind of problems in real world programming a lot. As I mentioned, I was not involved in this Bubble Cup, so I am not sure what's the case wih problem H. If the test cases are weak, then that is definitely not good and should not happen. 2. Organizers should definitely think about all approaches and solutions for the problem. But why do you think cat flaps are bad? Not trying to go through one is a also a skill a good competitor should posses, not just good algorihms and coding knowledge. Besides, competitors should not completely rely on constraints when thinking about solutions. When solving a real world problem, you do not have these hard constraints often. You try to come up with the best solution you can with a lot of unknowns. It's fine if you think cat flaps are bad and avoid them in your competitions. I just don't think that they are generally bad and that they should always be avoided.