Sure, the hard part is assessing, in any particular case along any particular road, whether the deer or the ditch will cause less harm; but that's a very hard decision for a human, too, given the small amount of time you have to grasp the situation and react to it.
I'm not sure I agree. I've certainly had to make thousands of decisions like that in my driving life. I was once in a multi-car situations where EVERYONE did the right thing and nobody got hurt. It only takes the brain a spit second to figure out that a deer is softer than a tree, and a treeless ditch is softer than a deer.
I actually think most drivers are pretty good, and usually paying attention. "Most" and "usually" are obviously nowhere near good enough, which is why all-autonomous vehicles would be far better.
Here's another angle:
They just re-set the timing on the stop lights near me. Now the drivers on the side roads, or turning left, have to wait what seems like an eternity, even if no-one is coming along the main road. Obviously some Mensa candidate at the highway department decided this would be "better."
Think about a road with no drivers, and all the cars had access to information from the cars around them.
There would be no need for stop lights. No need for stop or yield signs. The cars could whiz through the intersection from all sides, moments apart, never touching. Long before any collision could occur, the cars would have worked out the CPA (closest point of approach) and agreed which one would speed up or slow down to increase that distance to acceptable parameters.
Come to think of it, the whole idea of having proscribed, one-size-fits-all, immutable traffic laws would be obsolete. Traffic lanes, speed limits, none would be necessary as algorithms calculated the most efficient way for each vehicle to get from it's own point "A" to point "B."
There would be no traffic jams. These would be predicted, and avoided, before they could happen.
The best part is us old farts wouldn't have to worry about being trapped in our homes when we got too old to drive