Hindsight · review build · data not yet validated
Grammar checkers are now actually useful.
Grader A: partial
Grammar checkers were built into Word from 1992 and used by almost all Word users, so they were widely available. But in 2007 linguist Geoffrey Pullum judged that following their advice often made writing worse. Tools that most users consider useful (Grammarly and similar) grew only in the 2010s.
Test: Availability: built into Microsoft Word since 1992 (near 100% of office PCs). Usefulness: expert assessment in 2007 negative; widely trusted tools grew after 2009 (Grammarly founded 2009).
Grader B: partial
Grammar checkers were built into Microsoft Word from 1992, so almost every office writer had one in 2009. Their usefulness was disputed. Linguist Geoffrey Pullum wrote in 2007 that following their advice often made text worse. Grammar checkers widely seen as useful (Grammarly, founded 2009) grew into the mainstream in the mid-2010s. In 2009 checkers were ubiquitous but of limited quality.
Test: Test: over 20% of writers find grammar checking actually useful and rely on it. Presence: near 100% of Word users from 1992. Usefulness: contested by expert assessment (2007). Widely trusted checkers reached the mainstream after 2014.