I think we have to be relaxed when we play,composers notate on the score what they hear,so we have to make only the required movements that are needed in the particural bar line to create the right sonority.If we violate this,we create a wrong vision and a wrong sonority.Also some times this BIG BIG movements can easily turn into disaster,(imagine raising the hand or wrist very very high,try to bring it down with force(con bravura!!),a slight miscalculation will make you hit the c2,c3 instead of Bb2,Bb3,now what do you say?),and sometimes i have seen pianists stoping those big figures near the end and halt them,because they feel insecure about the jump,and you feel in their playing that they are insecure.I think piano playing is easy,but Good and excellent piano playing is VERY VERY difficult,like everything else we do (in all arts like painting,sculpture,poetry,it is easy to learn to write the words with correct gramar and no mistakes,-but the way we use them to make high works is something different).So those big figures are not what make the right sonority.Sometimes they are created even if we do not intead to do so,but making stunts only for the making of stunt moves is something musicless and bad for the us and the people who came to listen us.
Thanks for all the replies!!This has helped, but there's one last thing: what do people define as absolutely necessary when it comes to movement? Some people might say only move the fingers and wrist (slightly), others might say move fingers, wrist, and arm, while others might say move the entire body (these are all extremes in a way).One big difference is that some people I see move their elbows around alot for their wrists? (I'm not too sure about this technique since I haven't been trained in it) and other people play with elbows down and just use fingers and a bit of wrist swivel.