Most of an entire session? That's not going to enhance anyone's feeling of accomplishment.
That happens sometimes when the entire game is built around a variable-reinforcement reward system. The game is ultimately governed by dice.
Everyone eventually takes a turn at the table looking up rules for everyone else, taking extra pizza, and spending their actions posing in a hilarious way to show what they look like as a petrified statue.
The thing is, when it happens a few times, you tend to start looking up things that will prevent that state of affairs from happening again, thinking about spell choices and team strategies, reconsidering magic item distribution in the party, or even figuring out what to craft the next down time.
And, almost always, it's much better next time. That monster tactic gets negated a few rounds earlier, stopped cold right as it happens, or - in the best case - prevented before it even begins due to the right prep.
High level play is punishing, and demands better players.
And, solving a particularly tough problem creates a greater sense of accomplishment.