It makes no mention of the notion that during the cooling the walnuts might soak up all of the syrup, so that there'd be nothing left to pour over.
I sloshed in a lot of apple cider vinegar, right at the end there. I don't think it'll matter, because I think the walnuts were too mature anyway, but grr.
In other news, today has been lovely, and involved quite a lot of drinking-with-friends and not a lot of working. Hic.