My experience of ABS has not been good. If one wheel traverses an icy patch you effectively lose all braking as hydraulic pressure is reduced until the wheel in contact with the ice ceases to slip. This was my experience with a 20 year old Honda civic with an early version of ABS and things may have changed by now. Does current ABS have the ability to reduce pressure only on the slipping wheel?
ABS is not intended to improve braking distance. It is to improve handling under braking.
I've done one of those training days, and ABS will allow you to swerve while not having ABS may get you stopped faster, you will have run over the cones.
Often these systems are linked with other traction control, with varying sucess. Perhaps that is what you have experienced?
My civic 2009 didn't like one slipping wheel either.
Your claims are not accurate to the vast majority of real world road users:
https://www.nhtsa.gov/sites/nhtsa.gov/files/nhtsaabst4finalrpt.pdf "''DOT HS 808 875, NHTSA Light Vehicle Antilock Brake System Research Program Task 4"
The results of this study indicate that for most stopping maneuvers, made on most test surfaces, ABS-assisted panic stops were shorter than those made with best effort or full pedal applications with the ABS disabled
Despite being on relatively ancient vehicles most with retrofitted (and 3 channel) systems not representative of modern ABS/ESC/traction control.
You left off the rest of that quoted paragraph: "...The one systematic exception as on loose gravel where stopping distances increased by an average of 27.2% overall. Additionally, the vehicular stability during testing was almost always superior with the assistance of ABS. For the cases in which instability was observed, ABS was not deemed responsible for its occurrence."
It also states later: "This study also establishes that antilock brake systems include compromises of stopping distance versus vehicular stability. Most antilock braking systems maintain vehicular stability while braking by minimizing excessive yaw. In a curve, this stability may be created by sacrificing the shortest attainable stopping distance."
Note also that the study doesn't appear to even mention ice or snow, which IMHO are some of the most important situations for ABS to maintain steering control. (The PDF is not searchable, so I can't be sure without carefully reading it in its entirety, which I'm not going to do.)
So yeah, I think Jeroen3's statement that ABS is not intended to decrease stopping distance is correct, and my knowledge of the history of ABS agrees with him: the intent was to prevent loss of steering control. Note however that the study doesn't contradict that statement, either: just because ABS wasn't intended to decrease stopping distance doesn't preclude it also doing so.
Lets walk this right back to be fundamentals:
Dynamic (sliding) friction is almost always less than static (non-sliding) friction.
ABS was developed to take advantage of that and increase braking force
Ideally, individually for each wheel (hence the massive improvement in controllability)
To be accurate the first mass scale commercial applications of ABS were in aircraft where the only metric was stopping distance:
https://en.wikipedia.org/wiki/MaxaretComplications:
deep snow and gravel can have a "snowplough" mode where the assumption of letting wheels find their non-sliding grip results in longer stopping distances.
What percentage of drivers and roads is that? a tiny amount. What is the difference between ABS and not in those cases? Some 20-30% or so shorter stopping at the cost of directional control/stability. Can a driver in an actual emergency be cognisant enough to decide if they want to prioritise braking distance or directional control for the unfolding event? Unlikely, they'll just get their default unconscious reaction.
Ice is one of the areas that ABS (modern 4 channel systems) absolutely shines at. Most of the measured data is unavailable publicly (and the various "models" use stupid asymptotes that hide the complexity) but some does escape:
"Adhesion Properties of Studded Tires Study" Journal of Industrial Pollution Control 33(1)(2017)
The "I'm a
better[competitive racing level] driver and can always feel
and control the ideal slip ratio so ABS is worse than me" is the problem, as its pretty much implausible other than the specific corner case of
deep snow or gravel and wanting straight line stop without needing manoeuvring. Like a historic poster who claimed cars should have more power to weight (acceleration) as it would be safer.... in some vanishingly small corner case, and more dangerous the vast majority of the time.