Ah, an hour has passed, and I'm coated in gritty mud! Lovely! Hmm. I tried to rub it off - it just moves and stays stuck. Apparently coir has an almost glue-like quality I hadn't expected... Oh bother - try to rinse it off, and the unexpanded leftovers just slide and expand.
And the blu-tac dragon... I got bored at work. Blu-tac, the ultimate tool in procrastination! But I do finally have computer clearance.