learning to much at once ?

[ch0p1n 0wnz u]

hey

im learning la campanella, fantasie impromtu and chopin sonata no 3 finale, they are all hard songs, is it bad to learn them all at the same time or it doesnt matter!

just wondering how much pieces to learn at a time, is it better to learn a song one by one,  perfect one and move to the next or learn 3 or 4 at a time..

thanks