If we start there, where does it end ? Then it's unfair to use cannon fodder too, since that exploits the fact that the AI puts priority onto killing anything and thereby exposing the killer at the end of its turn. Weapons that can shoot through walls, grenades that stun, shooting at something remembered without seeing it, shooting at a suspected position without seeing it ? Unfair as the AI cannot do all of this. There are zillions of things that are unfair against the player, such as the damage scaling. This is war and war isn't fair. You just have to win by whatever means you can get your hands on.
That being said, you are asking me again not to write things into the forum so that I don't spoil other's games ? It is everyone's own decision whether to read what I call tactical tips and whether to read and use it or not to use it because e.g. the person considers it cheating.