While checking out the mens free skate starting order at the 2010 World Junior Championships, I noticed that the host country (Netherlands) skater, Boyito Mulder, was not on the start list. Even though only the top 24 men qualify from the short program, it used to be that Mulder would also be able to skate in the long program, even though he finished 45th of the 46 skaters.
I never really understood how that worked, even if it made sense to attract attention to the events in countries where there are no real strong contenders. By being able to skate in the long program, these skaters would (most of the time) remain in last place and in the final results be published as the 25th place finisher, which wasn't exactly true. Yes, they were the 25th ranked skater to finish the competition, but using this instance as an example, Mulder had 20 skaters in front of him that he would have passed over to receive that "official" ranking.
I'd imagine that the rule that changed host-nation skaters from skating the entire competition was probably in the same document that lowered the number of qualifiers to the long program at the European and Four Continents Championships, in the singles disciplines, from 24 to 20, but I definitely miss it.
EDIT 1:20PM: Rule Number 579.6 has been completely crossed out for this season, not allowing a host-country skater not previously qualified into a final free skate/free dance. Good to know!