The RaptureOfTheDeep has been known to manifest as a dreamy slowness of thought and apprehension that takes one by surprise, often when not engaged in pursuits requiring concentration or talking. A brief pause turns into woolgathering, and may result in a trance.
There are many locations where it is of great danger to become absorbed in the RaptureOfTheDeep, since one will fail to notice signals of trouble or passing time. Thus a Depth Guide is generally assigned to drylanders when wandering outside the DeepCourt proper. Ours was a friendly but insistent WideShuffler, a creature of the middle depths trained to simple tasks like herding.
I am fortunate in that my duties tend to keep me on task in these circumstances.
-- By AlfredReadyman
Commentary, footnotes, disputes, refutations, addenda, no-ways, yeah-for-sures:
If you see some lander staring into the middle distance, by all means snap them out of it. Make them recite prime numbers, tell you a story, give them some job or another, anything to keep them from losing their senses in the water. Really, most of all, if you're not confident in their ability to navigate the waters and use their adaptation, just keep them inside a structure!