You can find some big deductive proofs here: https://members.loria.fr/SMerz/papers.html https://members.loria.fr/SMerz/papers.html But you're right that deduct

You can find some big deductive proofs here: https://members.loria.fr/SMerz/papers.html https://members.loria.fr/SMerz/papers.html But you're right that deductive proofs are hardly ever worth the effort when you have a model checker. If you can get 99.99999% confidence for essentially free, most people wouldn't pay extra months of work to get to 99.999999% confidence.