I am a speech therapist and vocal coach myself and what I notice is that a lot of songs are sung in a lower key now. For example borderline, take a bow, express yourself, like a virgin, and so on. A lot of artists do this because your voice changes when you age. And there is notging wrong with that because most people won't notice. Her singing technique though lacks consistency. With Joan Lader during Evita she worked on her registers, but M still doesn't have good control over these as you can hear in Ghosttown sung live, when she sings "much" "dust" and for instance with Who's that girl on the Rebel Heart tour. And during a tour she starts to use more and more volume and in Madonna's case adding pressure under the vocal chords. That's when it appears she is yelling in stead of singing. That is why I don't understand they always tape one of the last shows when she clearly must know her voice be better in the beginning. And then there is the overusage and misuse of newly learned techniques. For me it was obvious she worked on twang and placing the voice before Hard Candy because the crow voice started then. The problem was that she used too much twang and sang too nasal. But she has gained more control over that now. The crow voice has kind of disappeared. On the other hand, at least she is emotive in her singing, and that is something you can't really learn. And she gives her all during a show.