Problem is that she's not just drinking at same time as eating, but seems constantly thirsty, e.g. she will be barking for water in the middle of the night and seeming desperately thirsty. She has no aversion to dry food, and will happily eat it (and will spend ages working for it too, e.g. kibble from a treat ball, but this also sets her off).

She's also a very confident dog who has never seemed very inclined to develop negative associations...especially where food is concerned, as she has always been extremely greedy. Given the chance, she would muscle in and steal kibble from my slowest eater, even after having her own wet food.

I think you should consider her age and that she might be developing some sort of dog equivalent of 'senility' or 'dementia' where there can be no good REASON for her actions?

Meantime you've solved the problem by avoiding the dry food. I was told it could tax their renal system when they are older anyway. My Cavvy loved the flat dish terrine type foods. But also enjoyed crunchy biscuits for treats.