The entire piece is an etude if you want to look at it that way. Just make sure the action is well-regulated because not all pianos allow the piece to be played.
On a sidenote, does anyone know whether the dedicatee of HR2 is one of Liszt's close friends or something?
This allow you to master every single technical difficulty in Romantic piano repertoire
Rubbish. Not to suggest they aren't worth doing, but there are technical things they do not cover and often other ways to learn the things they do.
Well. ok, please tell me what technical speciality they do not cover?
And possibly, what would be a nice way to study that particular weakness?