i don't 'try' to be a showman on stage, but when were on a big stage with a crowd thats diggin it i go pretty loopy, often sacrificing accuracy. but i don't care and no-one notices.
as far as energetic music goes, i doubt there will be many people in the audience who'll notice mistakes, let alone mistakes by the bassist (i mean, who pays attention to them?), and if they do the chances of them caring or remembering are slim. whereas a player whose clearly getting into the music and having a good time* will get that message across to the audience who, in turn, loosen up and have a bit more fun.
and finally, the reason i play music is to have fun. and i have more fun when i let go, and less fun when i stand still. so i very rarely do it.
*i know you don't have to lark around for this message to get across, but it helps