That's exactly what it is. She's slow, two-footed step sequence skater with very good gliding and great performance skills.Yeah, that just comes down to the fact that I don't think Kostornaya's Skating Skills are nearly as good as advertized, nor do I think her interpretation is even close to Shcherbakova's(I think Kostornaya has no musicality). You don't have to agree, that's why I labeled it as my opinion.
Thing is, Gleikhengauz and Tutberidze are masters of hiding their pupils' deficiencies or even transforming them into their (virtual) forte.
Their problem is, they do it so well, that some of their students start to believe those deficiences are not there anymore (!).