Kate Bush is one of the most influential artists in the world since her debut in 1978 and surely is considered as a prog related singer and songwriter. We don't need to search for long and tricky compositions to find the avant-garde habits and the musical research that are the essential elements of prog rock. Take this "Houdini", coming from such a beautiful album as "The Dreaming".
"The Dreaming" was one of the most creative albums by Kate.
All the tempo changes, the passionate vocals, the orchestral touches and, of course, the keen work on sounds make of this song a pure jewel. The chorus is heartbreaking and Kate is perfect when she digs very deep in the human soul as she does in this song. Is this progressive rock? I think so.