It’s the holding pattern that’s followed Clara throughout her lengthy tenure in the show—a promising glimpse of something here and there, interspersed with long periods of stalling, waiting for that next 'a ha!' moment to happen. Clara could have been a character that earned her two-and-a-half seasons of tenure. But with what feels like a season-and-a-half’s worth of story to her, we spent a lot of time with her that never actually amounted to anything for the character—something made all the more frustrating because when Clara was used well, in service of her own story rather than the Doctor’s, she could stand with the best of Doctor Who’s vast array of companions.