For reasons too boring to explain, I ended up in a nearby cafe for a late lunch and ordered 'rhubarb crumble and cream'. When it arrived it self-evidently wasn't rhubarb crumble, but it looked very pretty anyway, so much so that I took a photo of it. I poured over some cream, dug in my spoon, took a mouthful and .... bleurgh! So salty! I presevered a few more mouthful before I could take no more.
The waitress duly took my returned dessert - and my explanation - back to the (new) chef. It transpired there was a bowl on the pass containing a white crystaline substance he had assumed to be sugar, so he'd liberally sprinkled it over my dessert... It was, of course, salt.
So I guess there's a sermon in there somewhere, about not assuming, about judging by appearances, about not checking, and even about having the courage to speak out... at least no other customer will be served blackberry and apple with a side of sodium chloride!
They did bring me a new crumble, and it was delicious (even if still not rhubarb!) so all ended well.