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@gkelly I've only been watching since '94 so pre-'94 rules aren't something I know too much about - but, yes, this issue puzzled me in the past too.

)
Also at that time, BTW, the difference between what men and women were required/allowed to do in the SP was even bigger than it is now.
Men were required to do at least two triples in the SP, and allowed to do three if they could do a 3-3 combination.
Women were not required to do any triples -- 2-2 combination was still permissible at least for most of that time. At most they were allowed to do one.
And men were not allowed to do quads in their SP until 1999, although a handful of men had included attempts, some close to clean, during the 1980s, and more in the early 90s. Not to mention Surya Bonaly's attempts.
The spiral sequence was introducted to the ladies' SP in 1989 season, as was the mandatory layback, thus requiring female skaters to work on their flexibility or suffer in comparison to more flexible competitors. Men had a second step sequence and a change-foot spin with requirements that kept changing every two years until finally settling into required camel or sit position with one change of foot from 1995 season until now.
Clearly, what was required/allowed in short programs once the rotating very specific element requirements were eliminated after 1988 was not geared toward allowing the best jumpers to include all their hardest tricks in the SP, but rather to allow maximum content that more than one or two skaters were already including regularly in the freeskate, and also to allow minimum requirements at the lower end that average, as opposed to elite, skaters at that level (senior or junior) could be expected to attempt.
As the jump content in the freeskates has risen, so has the required or allowed content in the short programs. Exactly how many years it would take for something to be allowed in the SP after it had first been seen in the freeskate varies a bit, but in general it would be when several top skaters had already showed mastery of the skill, not just one or two outliers.
I was surprised the ISU allowed the solo axel in the ladies' SP to be triple starting ca. 2011, since only Mao Asada (and Yukari Nakano, who was retiring) had attempted it recently. However, it had been 20 years since Ito and Harding.