Sorry that its taken so long to answer your question.

George C. has done a good job of trying to answer your question, however, here is my 2 cents worth.

Generally, when I play I attempt to track the shuffle and isolate rich or poor segments. The easiest segments to track are often the bottom and top, however, occasionally I am able to track segments in the middle of the shoe. The problem with the middle of the shoe is that it requires better "eye balling". On the other hand, the dealer may make it easier on you due to the way he/she plugs or breaks down the shoe. Each shuffle is different and requires you to either "map" it beforehand or at least watch a few shuffles and create a map in your head real-time.

The best half approach is usually the method I would use if I can not track any individual rich/poor segments due to a complex shuffle. What I attempt to do is move as much of the poor segment to the back. For example, if I tracked a very poor segment early in the shoe (1st deck), however, the dealer performed a complex shuffle which essentially broke this segment into 3, I would attempt to make sure that at least 2 of these broken segments were in the back of the shoe. If I also isolated a rich segment somewhere else in the shoe I would attempt to make sure at least 2 of the broken segments of the rich segment were in the front of the shoe. To do this accurately you need to "map" the shuffle. Eye balling can be dangerous if you haven't done it before -- and even if you have done it before.

Your best results, obviously, will occur if you can use both poor and rich segment information and follow both segments through the shuffle.

Here are some guidelines I use:

1) I back count or count normally in a shoe while at the same time watching a few shuffles to see if tracking is possible.

2) I take a break and map (on a piece of paper) the shuffle if the shuffle is complex. If the shuffle is simple I simply map it in my head.

3) Only after I am confident that shuffle tracking is possible to me will I use this information.