My car drives way too slow with or without this enabled with 12.3.3. I have to press the accelerator at almost all times now. It's borderline useless. I want v11 back. What a letdown.
Yes, both modes are the same, ASSO (Automatic Set Speed Offset) & Manual. The only "auto" thing about ASSO is the way the speed offset cap is set
automatically at 50% over the limit.
Surface streets Cap Behavior:
ASSO: Speed offset +50% over detected limit. Hidden. Can be adjusted with scroll wheel (but is hidden, and may or may not be honored - not sure - recently I have not had it respond to this limit if current speed exceeds the invisible set limit). (The way to see what the limit is set to is to swap to manual mode on the fly, and it will display the current limit which is usually 50% over unless you have adjusted it.)
Manual: Speed offset set to your preference up to 30% over detected limit. Visible. Can be adjusted with scroll wheel.
Limited access highways & freeways Cap Behavior: *Uses v11 stack with that behavior, attempting to go to set limit*
ASSO: Speed limit is 5%/10%/15% over detected limit depending on chill/moderate/assertive style. Visible, adjustable with scroll wheel, and respected AFAIK.
Manual: Speed limit is set to your preference. Visible. Can be adjusted with scroll wheel.
In both Manual & ASSO modes, the vehicle decides how fast it wants to go, which may be a few mph over or under the detected speed.
This speed is not affected by the user offset in ASSO or Manual mode. UNLESS it wants to go ABOVE the Set Speed Offset value. In which case that value is a cap.
But the fundamental "auto-speed" is the SAME in both modes, AFAIK.
Upon manual accelerator input, both modes will tend to respect that input for a while UNLESS the vehicle speed goes above the set speed cap - in this case the car will rapidly regen back to the cap speed.
Advantages of ASSO mode:
Higher offset available. This is beneficial if you tend to want to go 30%-50% higher than the vehicle detected limit, since this is not possible by default in manual mode (would have to scroll).
Provides a different limit for highway driving than city driving so provides some additional flexibility.
Highway offset is adjustable on the fly with driving profile to 5%/10%/15% over the limit which is potentially convenient.
Advantages of manual mode:
Allows current set speed offset to be visible, adjusted, and honored. This is advantageous if you want to avoid speeding.
In the case of mis-detected limits much lower than the actual limit, it will allow adjustment of the offset so you can get up to speed. (In ASSO mode this may not be possible for very low detected limits relative to the actual limit; you would have to step on the accelerator constantly to maintain speed above the cap.)
On City Streets,
both modes lack the functionality of v11, which takes the vehicle to your desired set speed offset in the absence of obstacles.
This is a major regression from v11. The automatic speed is nice when your set speed is way higher than the speed one should be going, but this represents the minority of situations for many drivers. Again, that base automatic speed functionality is identical in ASSO and manual modes. That automatic feature is not what the "Automatic" in ASSO mode is referring to.
Again: In NEITHER mode does the set speed seem to have any impact on the speed the vehicle goes, unless the car NN happens to want to go OVER that speed (which becomes more and more rare the higher the % offset).
Corrections welcome. The may be some further subtleties to the framework that I have missed or not experienced. These basics are mostly correct though.