Comment by throwway120385

Presumably you test some things and use common sense for others. Like if you search for "grain filling oak" using an engine like Kagi(because Google just sells you the same product repackaged over and over) then you'll get people telling you variously to buy this grain filler compound that worked on their particular project, or you get people telling you to use drywall patch compound, or watered down wood filler.

The thing is, these things do produce some kind of result that looks like what you want. But it is still up to you to test these things on a project before you rely on them for whatever it is you really wanted them for, and that requirement doesn't go away just because you sourced the information from some LLM, or a book at the library, or Nick Offerman, or whoever else.