It's perfectly cromulent to hyphenate words this way. Doing so causes them to become adjectives. For instance, you would say "fast-paced agenda," not "fast pace

It's perfectly cromulent to hyphenate words this way. Doing so causes them to become adjectives. For instance, you would say "fast-paced agenda," not "fast paced agenda," or "fast, paced agenda." The latter two have a different—and in this example, weird—meaning. In this case, I think it's a poor style choice, because there are two verbs and an adjective being combined, but there's nothing 'incorrect' about doing so. It might be clearer to say "users who think they are technical," but fixing the mixed pluralization and incorrect use of "their" would go a long way on their own.