This is probably the one most important aspect that has to be taken into account to see the value in Al's work and PA overall! Al is a very discretionary trader and CONTEXT is the reason that keeps him away from trading in other ways.
The advantage of context is that, utilized appropriately, results in a very impressive win rate. However, most will not be able to appreciate Brooks' style and methodology purely because of the fact that "context" is not one single element that you note/observe. It is a collection of many components, which in turn have their own context imposed by other market activities. Once this part of Brooks' is understood, which I think may be the hardest to grasp, a trader should see a huge paradigm shift in their trading.
Most traders that see no value or disregard Al's method, may be doing so due to the context (among other things) not being understood in it's truest nature.