Why would you assume that "everyone" is using IJS throughout their structure? Absolutely untrue in the US. Here, the standard track free skate events from Juvenile. The Adult Gold/Adult Jr-Sr free skate events are supposed to be IJS as well. However, the Basic Skills/No Test/Pre-Prel through Pre-Juv/Adult Pre-Bronze through Silver events are judged under 6.0 using ordinals. All the freestyle-related events (jump, spin, compulsories, artistic, showcase, etc.) are under 6.0. (Pairs is structured similarly; I'm not sure when IJS is used for Ice Dance; I assume the higher levels as well.)
US non-qualifying Club competitions have the option of using IJS for all levels, but very few make that choice, afaik. I know that several clubs on the other side of the country do so; Sherwood Invitational is one.
The full-blown US IJS system is expensive to use for competitions because of the technology and additional trained volunteers needed. The paper-based "Modified IJS" would be good to use in lieu of 6.0 scoring, imo. Ordinals are meaningless and often swing widely from competition to competition. I'd rather the skaters get a solid numeric score so they can set goals and strive for "personal bests" before the next event. It would be wonderful to get an element-by-element plus overall score, like the old ISI results, but I suspect it's too time-consuming.
The USFSA Continuing Education Requirements (CER) are required for any coach presenting students for tests or competitions. There are two tiers: CER-B for those whose skaters are not competing in qualifying events and CER-A for those with qualifying-event skaters. The difference is simply that the qualifying coaches have to take an IJS course. There are a number to choose from, including "Current Season Singles Skating," which outlines things like spins with 3 revs in position, difficult entries, step sequence vs. chore sequence, etc.
I don't have any skaters at the qualifying levels, but I comply with CER-A each year to pick up additional knowledge for the future, even though it costs an extra $25. I bring that to my lower-level skaters since many judges have indicated that they use the IJS standards to judge tests and 6.0 events.
One note: just because a skater doesn't do three revs in each spin position doesn't indicate the coach was ignorant or the choregrapher blew it - sometimes, it's the skater's fault. You have to know that the elite skaters at the ISU Senior Grand Prix know they're supposed to do something. There are any number of reasons why they give away points.