It would be more efficient to do multiple hypnosis-bound study sessions (letting her forget everything between each) before restoring the memories. Then you can get several hours worth of studying in before she's hit with the mental exhaustion of having done it. You just have to make sure that none of them rely on the knowledge from the other sessions.
And then who cares what happens when she's suddenly forced to take on the burden of all that at once in the span of less than a second. If she ends up in the hospital, who cares so long as she passed her midterms, right?