RPGMemes

don't let the country bumpkin make Arcana checks about monsters he's never seen

Why not? It could be fun! Of course non-critical rolls would be useless, but on a critical failure they could convince the whole party that dragons can't see movement, and on a critical success they could buy mere chance figure out where its voonerables are (it's a million-to-one chance, but it might just work!)...

or let the stick figure try to punch down a wall

Again, why not? All rolls, they take a bit of damage; critical failure, they break their arm or hand, and manage to dislodge a brick which starts a comically unlikely and extremely noisy Rube Goldberg chain reaction which ends up waking up and alerting all the guards; critical success, they hit the hidden button that opens the secret door (in another wall), starting a whole new subquest.