Slanting the deck in a controversial debate

Sometimes, two things will be compared in a manner that is unfair, because it gives a misleading representation of how they work in reality. The two things - and they could be anything from food to political/philosophical views - will be like (so it's not a Faulty Comparison per se), but the way they are compared is poor. 

An example is a person saying, "optimism drives you forward, keeps you motivated, and is good for your mental state. Pessimism causes you to give up without trying, makes you feel sad, and will end up hurting you in the long run. Therefore, optimism is better than pessimism." Here, the speaker has taken the best parts of optimism - the ability to stay motivated, effectively - and contrasted it with the worst of pessimism - the possibility that one may give up on an achievable task because of it. The comparison is thus misleading as it does not fully explore the elements it purports to compare.

Logical form:

A and B exist as comparatives.

Positive/negative aspects of A are emphasised.

Negative/positive aspects of B are emphasised.

The newly-emphasised A and B are then presented as opposites.

Therefore, A > B or B > A.