Oh! Indeed, I completely missed out on the whole meat of your argument. I'm completely with you here: why on earth would invisible text be a standard error method?! *boggles*

More often, I'd probably just offer them access to my recipe file and check on their progress periodically.

*snorts* Am exactly the same, tbh.

I wouldn't feel as though something were missing. I might wonder if they hated my cooking style, but wouldn't be inclined to change it.

I really like how you build up the metaphor; it rings very true to me. Now I am itching to write a story with asexual!Snape along these lines . . . O_O