I think a lot about Jill Trenary
Most of what is being said is true: She maxed out at a 5-jump LP which was generally the number of triples planned by the leading women through Calgary 88, except for Ito planning 7 triples. But Thomas had a planned 3T-3T and Manley had a 3Z, which meant Trenary wasn't at the forefront.
In 1989 and 1990, Ito was easily the #1 talent in the world, but with retirements and such, Jill maintained medal status because the ranks were thin internationally, and there was no big explosion of talent in the ranks behind Ito: The USSR and GDR didn't have any notable newcomers. Witt had retired and for the 1st time in decades, Jutta Mueller didn't have a serious threat on the world scene. There was no other strong competitor from JPN, or anyone from Asia for that matter, and no CAN woman. The best outside of Ito and the US women was Claudia Leistner from FRG, who won Euros and had similar jump content to Jill, but was a little more wooden. I always felt that US and Intl. Judges liked and preferred Jill to someone like Claudia. It gave her solid footing for a WSM in at least 1989.
As has been mentioned, Kristi was more technically ambitious but she still was developing the artistic mark in those first years. I think that Jill skated with command when she was 'on'. Consider there was a stronger pecking order back in the day under an ordinal system using 6.0, plus CF allowed Jill breathing room against Midori and Kristi. It's not hard to see Jill capable of snatching silver at that time. Also consider Kristi was straddling Pairs and Women. I think that the USFSA was solidly behind Jill at the time which meant she may not have had to work too hard to stay in front of Kristi
In 1990, Midori was suffering from bad figures and injury, and Kristi splatted x2 (?) in the LP, while Jill probably had her best LP ever, which gave Jill the opening to win. The cards fell the right way for her to be a World Champ.
More than anything in the following years, the development of US women doomed Jill's chances for another Olympics in 1992.