Just to get the details straighter:
Oh yes it has--but only in ice dance. The first instance I can remember was when Renee Rocca teamed with Gorsha Sur. Punsalan and Swallow allegedly tried to block Gorsha's citizenship so he couldn't go to Lillehammer, because they (P/S) only did well enough to qualify one team to the Olympics.
It was Roca/Sur who "only did well enough (at 1993 Worlds) to qualify one team to the Olympics." Punsalan/Swallow's only previous Worlds appearance had been 1991. But that was pretty much par for the course for US teams in that era.
http://www.eskatefans.com/skatabase/worlddance1990.html
1991 Munich, GER
9 April Sargent/Russ Witherby USA
11 Elizabeth Punsalan/Jerod Swallow USA
1992 Oakland, USA
9 April Sargent/Russ Witherby USA
15 Rachel Mayer/Peter Breen USA
1993 Prague, CZE
11 Rene Rocha/Gorsha Sur USA
15 Susie Wynne/Russ Witherby USA
And afterward:
1994 Chiba, JPN
12 Elizabeth Punsalan/Jerod Swallow USA
1995 Birmingham, GBR
10 Rene Rocha/Gorsha Sur USA
1996 Edmonton, CAN
7 Elizabeth Punsalan/Jerod Swallow USA
14 Rene Rocha/Gorsha Sur USA
I don't know why this site has Roca's name misspelled as Rocha.
The return of professional skaters (Roca, Sur, and Wynne were all reinstated pros) and the breakup of the Soviet Union sure changed the competitiveness of international ice dance from the early to the mid-1990s.
The second was when Belbin/Agosto were the second-best team in the US (and the fifth-best team in the world). A bill went through Congress that, if passed (eventually it did) would give athletes and individuals who are contributing to American society in a great way a fast track to citizenship. One of the lesser-ranked dance teams' parents tried to push a bill that would have blocked it.
In 2002, Belbin/Agosto were the #2 US dance team but since Belbin was not a citizen (and was too young and had not been in the country long enough to qualify for citizenship), they were not eligible for the Olympics. They did compete at both Junior Worlds (where they won gold, completing their rise from bronze to silver the previous two years) and Worlds that year.
In 2006, Belbin/Agosto were the #1 US dance team and in fact were the reigning
world silver medalists, the best result ever for a US team at that point. That was the year that there was a push to expedite her citizenship and that another team's parent opposed (although the opposition may have been more to eliminate competition from Max Zavozin, whose citizenship was also affected by the bill, than from the reigning US champs and world medalists).