The marking standard seems to vary depending on who is skating (and always has) - the flashiest performance always seems to score highly despite any lack of actual skating technique and ability....
Bonnie in series 1 couldn't sactually skate for toffee - but was always high - usually top - of the leaderboard because of her performing skills and it has been the same all the way through subsequent series - although in the end the most deserving skater usually gets the crown!