Many philosophy problems involve imagining hypothetical scenarios. At times there has been significant debate over the validity of this.
At times there has been significant debate on Less Wrong about the relevance or value in discussing hypotheticals that would never occur in the real world. In The Least Convenient Possible World, Scott Alexander suggests that ignoring hypotheticals often means that you are technically correct at the cost "missing the point and losing a valuable effort to examine the nature of morality". He suggests that considering about the least convenient world is often vital for allowing us to discover our true motivations and often leaves us too much "wiggle room".
In Please Don't Fight the Hypothetical, TimS suggests that fighting the hypothetical is equivalent to, "I don't find this topic interesting for whatever reason, and wish to talk about something I am interested in." He says that this is fine, but suggests it is important to be aware when you are changing the subject like this....