All a polariser does is reduce glare and improve contrast, it can do nothing to change the degree of apparent target movement caused by refraction (mirage). If you think about it, all you are doing is to alter what is perceived by the eye, you can do nothing to affect the conditions between sight and target that give rise to refraction. What you might achieve with a polariser is to reduce the apparent elongation of the aiming mark by virtue of the reduction on glare but you can do nothing about the refraction that occurs in the cylinder of air between you and the target. If anyone tells you differently, ask them to explain the physics that underpin their answer.
Rutty