I went to the science direct site, an interesting article that along with your intial comments, has me puzzling.
The application of sodium acetate that I thought I knew, is that of a solution. I used to make it for lecture demos when I was a university chemistry technician. It's a long time ago, but I think it was around 50% vol/vol with water. I used to boil it, and then put it to cool. All this had to be done in very clean glassware. Dropping a 'seed' of solid NaAc into the beaker would cause the 'supercooled' solution to instantaneously crystalize to solid, at which point it would give out loads of heat. (actually, the favourite use was a conjuring trick; pour the liquid into a paper bag containing the seed, and then scrunch the bag up, it looks like the liquid has vanished!).
Now I'm not so sure.
The uses I've found today in various articles are using the NaAC not as a solution, but seemingly 'pure' stuff that is melted. I'm wondering now if I was mistaken all these years, and that in making my 'solutions' I was actually making the trihydrate form.
Either way, as you say, it needs a lot of heat to get it back to liquid.