I'm rewatching The Snowmen and I've always thought that it's silly that when Clara is asked for a singular word to get the doctor to help she says "pond". It just feels a bit contrived. But we never actually hear Clara say it; we just hear Vastra tell the doctor that she said it. This got me thinking that it feels more likely that Clara said a different word, Vastra knew it wouldn't be enough, Clara explained her plight involving the pond, and Vastra realized she could get the doctor out of retirement by lying to him. We'd already been told multiple times that Vastra and company is against the doctor's isolation/apathy and I could see her being willing to lie to get him out of his slump. Thoughts? Sorry if this is already a popular theory that I'm unaware of.