I agree though with tulosai that it is puzzling that KA are not efficient in building really successful senior teams. I bet someone has an explanation, I just don't have one. I don't think it is just the lack of political power, as I am not even sure that is it. They should have political power, they have been around a while and they are good coaches, especially for juniors.... It is puzzling.
In fairness, they had a chunk of not great luck, and success on the junior level doesn't automatically translate in dance at all into the senior level: if you go back through all the medalists at JW dance over the last 10 years, out of the 27 teams that have medalled, only 5 translated that into a senior World medal. In comparison, across ladies there have been 20 different junior medalists and 8 of them have gone on to senior medals. And it's not just Kustarova that struggled to take successful juniors to a strong senior career - Kaitlyn & Jean-Luc haven't set the world alight, Paul/Islam are going nowhere, S/B have been top of the middle of the pack but no better in their 3 senior seasons.
For Kustarova's junior teams (excluding Romanovskaya because I know next to nothing about their career): They did OK initially transitioning B/S, getting 13th at Worlds, then they had a rough 2nd second, but came back to make the Olympic team, and then had two years as national champs & winning Euro medals. Worlds 2012 was a disaster for them, and I wonder how much of their decision to go to Zhulin was a panic because of that & fear of losing ground to I/K, or more general dissatisfaction with KA. Since the switch, they got a world medal, but then slipped way behind I/K, and if the great partner swap hadn't happened I don't think they would have been able to reclaim the Russian no. 1 spot.
M/K were really unlucky with him getting mono at the start of their 1st senior year, and their switch to Zhulin hasn't produced anything miraculous.
S/Z won a GP medal in the 1st senior season and then in the following season finished fourth at Euros and got onto the Olympic team ahead of two much more established senior teams. And we all know what happened next, and you can't lay the blame on KA for that.
It's too early to write off Kustarova with Y/M. They haven't been all that technically solid, but Anna had a horrible injury. The FD was a mis-step, but I really liked the SD. I see them kind of where S/B were in their 1st senior year - it's not a disaster at all, and it always always takes ice dance teams longer to get established than single skaters who if they have a technical advantage can quickly make a splash like Evgenia or Boyang.
Where they do fall down I think is the packaging and presentation: the things that makes a team easy to like for the judges. Y/M's FD this year was ridiculous, WWRY never worked for I/Z, and it didn't help that I always felt their costumes looked a bit sloppy, drab, & obscured their lines, my mind will always be haunted by Bobrova trying to do a samba dressed in heavy black velvet... It's easier to get away with this at junior level where good SS trumps everything, but when you get to the crowded senior level everyone has good SS, all the other stuff adds up to the overall impression and that's reflected in the scores.
It's not about political clout, but more being the kind of coach that thinks "how can I make it as easy as possible for the judges to give this the highest possible marks". Igor does this with his programs for C/B; I find it largely boring, but it shows off Madison's flashy personality which is the strength of their partnership. Marina has with S/K - Victoria still has terrible basics, but it helps that she's now wearing more streamlined costumes which help make nicer lines instead of the Kustarova ruffles everywhere. D/L have done it with P/C: if you watch their Zazoui programs they skated much more closely together and in more complex holds, after they moved to Montreal a lot of the in between moves were simplified and there is a lot of space between them in hold - this allowed them to increase their flow and speed, which the judges notice & reward more than the previous complex work, and also has reduced the amount of mistakes they make, thus building up their reputation. It just doesn't seem to me that KA are taking this approach of wringing every possible point out of each program - or maybe they think they are but the understanding of what judges are looking for is way off.