If this info can help anyone else, I'm happy. 2007 TL, well maintained, all new rotors, pads, new fluid, Michelin MXM4 tires, 90% tread. At about 30 mph on a hot dry summer day, an elderly lady coming from the opposite direction decides to cut directly in front of me and tries to enter a service station on my immediate right. She realizes her error, a tad late, and freezes like a deer in the headlight. This is an accident with no escape route. Hit the brake pedal hard enough to bend it, at least it felt that way at the time. ABS kicks in but unfortunately for a panic stop on dry pavement where steering is not needed, ABS will not stop as fast as 4 wheel lock in an a non-ABS vehicle. Which of course is an option I did not have (although if anyone has figured a way to turn ABS off at the dash, God Bless You). So 4000 pounds of car under control of ABS computer braking plows into the offending vehicle, does major damage to her car, leaves it disabled, blown rad, pushed in fender. On my car, hood buckles, lots of trim damage, a rad mount shears and a headlight loosens. So far so good. Except after the accident my well-maintained brakes suddenly felt weird. Start with the internet, Google "panic stop" and "master." Find that other car companies have clearly acknowledged a panic stop can in fact trash the master. Rare but it happens. Depends how much force you used on the pedal to try to avoid the accident. Next stop my own mechanic who test drives the car and writes an opinion for the insurance adjuster saying the brakes which had been perfect the month prior were mushy at stoplights. He believes that the pin in the master had been forced to the full end of its travel. Since over the life of the car the pin travel in the master "wears in" according to the driver's habits, this means the pin was forced into the bore to a degree it had not travelled since it left the Acura test bench in 2007. Over the years the bore would accumulate small notches and grooves which in the normal course would be harmless, ie, in day to day use. However in the panic stop, forcing the pin into parts of the bore it was not "used to" it may have damaged the seals. Even the smallest seal damage would affect the braking. Might not be felt in a fast stop but at a stoplight for example there would be some small slow leakdown and a corresponding mushy feeling. Letter convinces adjuster to allow local Acura dealer to do more tests. Dealer confirms brakes feel mushy. All four wheels are pulled and each set of pads is individually adjusted and lubricated. System is bled. Brakes still mushy. Problem not found. Since you can't x-ray the master on the car, the diagnosis is done by elimination -- the only part of the system that could still be causing the problem is the master so there must be some seal damage. New master installed, insurance pays as part of the accident. Mushiness gone. Afterthought, with a car this heavy, you want your brakes at full operational capacity at all times. Overall consider myself lucky. Otherwise after the accident, the car would have been pretty on the outside ... but dangerous on the inside. Afterthought no 2, not generally known but when ABS was coming in, GM fought long and hard to stop it. They hired race drivers and sent them around the country on Corvettes specially fitted with switches to turn the ABS on or off. In most panic stop situations, the drivers could beat the ABS time and again. Nobody cared. GM lost the battle. ABS is here. Now drivers go faster and tailgate because they feel invulnerable.

 

Huge wall of text. Cliffs?

 

Accident, smashed brake pedal to floor
Car fixed, mushy brakes
Multiple mechanics confirmed mushy brakes
Replaced master cylinder fixed mushy brakes
Insurance covered it as part of accident
Random rant against ABS

I think that sums it up.

ABS may increase stopping distances in various situations but without a doubt it overall is a good thing to have. Most people in a panic scenario will not properly modulate their brakes. Even the best drivers will not react properly in a panic scenario and will just mash the pedal to the floor. I personally have had ABS save my arse a time or two over the years....but mostly in rain or snow not related to stopping distance but the ability to keep the car going in the original intended direction.

 

I depress the brake pedal fully with significant force frequently. My brakes are not mushy.

I consider it to be a very good idea to occasionally stand on the brakes as hard as you can. Preferably do it in an area and at a speed so that a failure would not be significant. Have a backup plan.