My argument was that the third-party package is what's key here. Merely converting your querysets to a list in code before handing it off to the template won't

My argument was that the third-party package is what's key here. Merely converting your querysets to a list in code before handing it off to the template won't fully protect you against extra queries. I'm not necessarily trying to avoid third-party packages, in fact I've installed the package you suggested in one of my projects and will be trying it out.