So few people actually understand what goalkeepers do in training, it is a constant process of working on technique and refining the way they deal with certain situations. My lad has had seven or eight different coaches in 6 years and each one will have a different perspective on everything from hand position when getting set, to techniques for 1:1's and all other aspects.
Pepe has a very particular style, one my son has followed and different coaches differ on the pros and cons of this. Pepe used to drop one knee to form a barrier when dealing with 1:1's however this has changed recently, to in my opinion a less successful one. Pepe is one of the few keepers to employ an effective side volley, which can be accurate but is far more difficult to master.
To say keepers should just remember what they have learnt, however tongue in cheek is being too simplistic and not fully understanding of how much work keepers constantly do with their coaches.