Deer whistles work fine. Making them freeze in place is the point. You know where they are and can drive around them. If you let them decide which way they are gonna go, they choose the direction your car is in every single time.
Here's a hint. The deer whistles don't paralyze the deer. You go to drive around them, they just run that way. The surest way to not hit a deer is to aim for it, unless you're counting on that. In any case, the deer don't give one shit about deer whistles around here. Presumably, they're used to them. The ones too dumb to get out of the road to begin with are too dumb to learn what a deer whistle means. By the time they figure it out, you've already run them down.
I actually live in deer country and have never hit one (knockonwood) and suspect the primary way I've achieved this is to pay attention. I've only ever seen one hit, though it happens all the time around here. The one I saw hit was hit by a truck right in front of me who wouldn't get the living shit out of my way on Bottle Rock Road, but he thought he was fast so he was outdriving his ability and BLAMO. The deer avoided the trash truck coming the other way, but he nailed it with his right corner, meaning that if he'd simply seen it and slowed a bit, he'd probably have missed it. I guess I won that round, whee.
We need to relax hunting regs to a no bag limit. They're like pigeons around these parts (TN) and everyone is tired of them jumping in front of their cars.
Well, I don't know what it's like where you are, but the general lack of water is playing hell with deer populations here. They seem thick, but illegal poaching is rampant and they're really concentrated around civilization since that's where the water is.