First let me state clearly, I love Almodovar films. I totally recommend Dark Habits (DH) to anyone interested in film directing or like me merely wanting to observe the development of creative genius. This is NOT a film I would recommend to someone who has not seen and loved Almodovar's later works. DH is certainly not another Volver or nervous breakdown.
Owning Pepi Luci, Bom (PLB) I already realised that Dark Habits would be more about a director learning his craft than a good film and so it proved. Although the humour, characterisations, direction and budget of DH is already vastly superior to that of PLB it does not possess the finesse of the later films.
DH is one of those films that improves upon better acquaintance. Although the plot resolves itself on first viewing it is far more satisfying second time around. During the first watch I found the actions of the characters too bizarre to make sense. I needed to see the film a second time in order to understand their roles in the story. I can easily imagine someone with direct experience of the Catholic faith could find far more in this film during subsequent viewings. Twice was enough for me but that must make it a good film as there are not many films I want to watch twice in quick succession.