Earlier quoted context omitted.
In non-life-or-death situations, people endure quite a large amount of discomfort to achieve other goals. But a high-enough level of discomfort kills people. Does this mean the ones enduring small amounts are irrational? Reducto-ad-absurdum is a proof only when it takes into account everything in the argument. In life-or-death examples, other normally-included portions are dropped, making the argument something else…
It's not a straw-man. I have attempted to refute nothing. I was merely asking my parent to consider how he might behave in such a situation. I used a different situation, it is true, but only because I have found being on the instructional end of cheating feels very different than you might imagine, so I guessed my parent was not familiar with it.
As a student who has not cheated, but has had to sit through countless lectures about cheating, and a few where large portions of the class did, I ask you and (other?) teachers this question: to whom are you teaching? The ones who are learning, or the ones who are cheating?
I understand that you're stuck with both, but either find motivation in the successes or consider another line of work - it's part of the job. Otherwise you're screwing the ones who did the right thing.