I have never used abs except in my car. I believe it activated before skidding would occur.
On motorcycles good braking habits are very important. Using both brakes is a habit to build, because if you try to do the Freddie Spencer front brake only you will lose in an emergency stop situation.
You need to practice panic stops, shortest stop possible from different speeds and even practice braking in corners or turns in an empty parking lot. What ever habits you train and learn is how you will react in a panic situation. you can not drive around looking at the scenery for 10,000 miles and figure you will react in your favor when something goes wrong on the road. So do concious training. Try the brakes seperately, then use them together. Then us them hard together. then build the habit of using them together all the time.
The same with countersteering. Train your brain and muscles to work to gether counciously. when you turn left think 'left turn' as you push the left handle bar. same for right turns. make your brain and muscles get involved together with the simple tasks, so it becomes the reaction you want. Instint may not be enough.
Some years ago a bike mag had an article that new riders were actually steerig into the problem in panic situations, because you dont have time to think about countersteering, you have to react. The riders for example would 'turn' right to avoid the problem to the left, and actually initiate a left swerve.
So for the cabs, it may be more iportant to usse both brake becaus I a not sure if you get full front power using the front brake lever alone. It looks like the rear brake adds some braking power to the front, but also not enought to be used alone. I dont know that abs save lives more than good practice, it may. But dont let it become a crutch.
I have riden alot in the rain, and you would be surprised at the amount of available traction, you have to try it. and like all practice, start easy and work gradually. I went down on black ice, because untill that day I had no idea what black ice was. I was leaning,and braking for miles. But I kept getting very wide out of the corners, I thought I was doing something wrong, tried adjusting my lines and finally went down.
So even though there was still surprising amount of traction for me, ice is a no go. I plan on riding the 250 sanely, and do not feel the need for abs. If I was buying a 1000 or 600, I would definately want alll the goodies.