I Agree, I have a gaming mouse that allows me to turn around and kill players with a minigun, but if im Immobile i'll take atleast 2 seconds to spin around, which would lead to the death of me.
I don't think you understand, being immobile, in this context, would mean you would be a machine gun, just unable to move around, but still be able to swivel 360 in order to sweep whoever is around. It would take the same time to spin around immobile as it would without it.
Well, if you have to go get someone thats hiding in a building or something, they will just peak and kill you because your not holding the minigun, which will give them easy kills if your as Still as Stone
This brings in the factor of unfairness, as people with proper gaming mice and nice scrollers have a huge advantage.