Skaters often practice harder jumps in order to improve their other jumps.
For example, Gracie Gold's latest Instagram video today shows her landing a 'Rippon' triple Lutz and flip (new for her) in practice: http://instagram.com/p/bElEU_rAvT/
Courtney Hicks landed a 3F with her arms overhead in her 2013 Nationals exhibition.
I forgot to link to this news thread I started in GSD earlier this week: Wagner picks Arutunian to join coaching team
Also, USFS posted/tweeted this video link last week as part of their "Throw Back Thursday" #TBT series:
"Christina Gao provided U.S. Figure Skating this video of her pre-juvenile FS from the 2004 EGL Regional." http://www.youtube.com/watch?v=80gwDOUe88Q