In a tight berm you throw as much of your weight into the lean as you can get away with. Countersteering in my opinion (the actual act of turning against the corner) is for when you have leant (or positioned yourself on the bike in such a way) so far as to actually break traction and the back wheel is finally starting to overtake the front. By counter steering you are able to catch the rear. Other people have said and actually use it to initiate a tight corner, I do not do this yet still like to think I can lean in hard and still make tight corners. You are correct in saying you push the bars away from the corner but this is because the lean pushes the bars inwards and the more you lean, the harder you must counter this, therefore it can be considered counter steering but not in the sence you actually turn the bars. The only time I initiate a corner with counter steering is on long open fast corners and I want to slide instantly, I lean into the corner and turn away, this is almost guaranteed to make you drift or if you are not careful will force you arse over tit.
However you must realise it is possible to hold a drift and NOT counter steer. Here are two pics of me hitting the same corner. The first one I drift through the corner with both wheels and the front wheel is not pointing to the outside of the corner. in this photo I did almost lose it while showing off for the camera
and pretty much had to do a small dab. It is actually an ugly slide this one because it is on a rather large bank, on flat it looks much better.
The second photo I manage to hold traction yet still lean it over even further. The two shots I have completely different body language, this one I have tried to lean the bike over hard while keeping my body more upright. This leads to more grip through the tyres. I also do not lean as far forward in this turn while keeping traction, if you want to slide lean forward much more and twist your hips more. I also a,m trying to slide my tyre by using the outside pedal and putting as much force through it as possible.
