I drove for the first time with Tesla's FSD version 12.3 last night.
For translation: 3 mph = 4.8 kph; 10 mph = 16 kph; 15 mph = 24kph; 25 mph = 40 kph;
30 mph = 48 kph; 40 mph = 64 kph; 1/4 mile = 0.4 km
We drive on the right, so an early and 'lazy' left turn puts us in the oncoming traffic lane.
The bad news:
1) I 'almost' intervened when it crossed into a double-yellow-line surrounded no car zone which the car crossed to get to the dedicated left turn lane. (Other drivers regularly do this, but I do so only when stopped cars in the lane prevent me from getting to the turn lane legally - there is a dedicated left-turn light that is only activated when a car is at the turn lane's stop line, and the turn light precedes the straight-ahead light - and the intersection has an appox. 3-minute light cycle.) I didn't intervene becasue the car did not get into in the on-coming traffic's lane.
2) When moving into a long dedicated right-turn lane, v.12.3 moved half way into the turn lane, then moved a quarter of the way back, then moved fully into the turn lane (no other cars were nearby); v.11 hasn't done this sort of thing for a long time.
3) At a non-intersection where the road takes a sharp right turn (signage, including on the road surface, and a flashing yellow light you'd hit if you went straight), v.12.3 slowed to 3 mph well before the turn. (I let it do its thing as there was nobody behind me.) When going the other way on the same road earlier (a sharp left turn), v.12.3 drove appropriately, as v.11 always did (both ways), slowing to about 10 mph.
4) Near my home, it drove off the narrow dirt lane and stopped (still half on the road but heading toward the end of a short hedge that lines the lane); it was going only 3 mph in the speed limit 10 zone before it stopped. (While stopped I 'intervened.') Under v.11, FSD either jerked back and forth within the lane (obviously uncertain, but proceeding because I had my foot on the accelerator) or, with earlier versions, FSD just disengaged (with the alarm).
The good news:
1) All intersection turns were smooth and well timed. (One place FSD v.11 always (wanted to do) did a very lazy left turn, getting fully into the on-coming traffic lane at a blind corner, v.12.3 stopped at the stop line, proceeded straight at a crawl until it could 'see' around the corner [then fully stopped briefly - why? there was no other traffic] and then made the turn in a non-lazy manner.)
2) There was no (trying to) getting into dedicated turn lanes when we were going straight.
3) The repeated (under v.11) funky (some indecision) behavior on a very wide driving lane at a railroad crossing went smoothly.
4) The FSD v.11 used to always get in the right lane when a single lane turned into two lanes (regardless of other cars' choices); v.12.3 choose the left lane, which was just fine (both lanes were backed up).
5) The FSD v.11 usually choose the left of two dedicated left turn lanes at an intersection, but as we have a right turn a quarter mile after the left turn, I prefer being in the right lane; v.12.3 choose the right lane.
6) My neighborhood has multiple 10 mph signs posted (We mean it!); v.11 originally treated them all as 25 mph, but a couple months ago treated the first sign as a 10 mph but all others as 25s; v.12.3 read them all as 10 mph. (Yeah!)
Other observations:
1) I set the speed control to automatically go 5% over the speed limit (if, of course, speed control is engaged) but manually adjust it according to typical driving conditions on different road sections, from exact speed limit to 15 mph over (after a traffic circle where the posted speed limit doesn't go up for a quarter mile). V.11 almost always went with my 'decision' (other traffic allowing). V.12.3 sometimes didn't get to my desired speed, choosing somewhere between the posted speed limit and my setting.
2) Along one section of rural road along which I travel both ways, the posted speed limit in one direction is 30 mph and in the other it is 40 mph. Under v.11, it read the posted speed limits; under v.12.3, it "knew" the speed limit increased to 40 (where the speed limit decreases in the other direction) and set the speed control accordingly.
On the whole: incredible improvements!
