[noud]

I had exactly the same feeling when reading this blog. Sure, the techniques used to find the solutions are really interesting. But the claim more than they achieve. The problem statements are not available in Lean, and the time limit is 2 x 4.5 hours. Not 3 days.

The article claims they have another model that can work without formal languages, and that it looks very promising. But they don't mention how well that model performed. Would that model also perform at silver medal level?

Also note, that if the problems are provided in a formal language, you can always find the solution in finite amount of time (provided the solution exists). You can brute-force over all possible solutions until you find the solution that proofs the statement. This may take a very long time, but it will find the solutions eventually. You will always solve all the problems and win the IMO at gold medal level. Alphaproof seems to do something similar, but takes smarter decisions which possible solutions to try and which once to skip. What would be the reason they don't achieve gold?