My apologies, it seems to have been a random fluke.

I noticed that it was happening to my mummy, in which case I suppose it would make sense for her to be soaked due to her unremovable bandages.

Anyway, it seems to be working with my normal sims fine now. Sorry I can't repay you for your lost time.

I'm very pleased that my sims get the soaked moodlet from "shower in a can" but not so pleased that they get it from taking a bath. I suppose a -5 moodlet really is not a big deal at all, but it becomes an annoyance when puddles pop up everywhere and another negative moodlet appears for the messy surroundings. I'm quite sure that having my sim take a shower instead circumvents the soaked moodlet but then the rubber ducky and tranquil moodlets can't be accquired.

Is there an option to turn this off that I missed?
Or should I do more poking around and check that I'm not just being a tarded n00b?