I can actually answer this. The training data went through a team of grammarly writing experts before being fed to the AI. Writing experts would get short snippets out of context, often from publicly available text (e.g., reddit comments, classic novels, poems, scientific papers) and correct it for both grammar and clarity, then that would then become training data. Later on the team would do the same for content generated by the AI.
Source: Was one of the writing experts. For a couple of weeks I was correcting snippets that were very very obviously from r/squaredcircle
I can actually answer this. The training data went through a team of grammarly writing experts before being fed to the AI. Writing experts would get short snippets out of context, often from publicly available text (e.g., reddit comments, classic novels, poems, scientific papers) and correct it for both grammar and clarity, then that would then become training data. Later on the team would do the same for content generated by the AI.
Source: Was one of the writing experts. For a couple of weeks I was correcting snippets that were very very obviously from r/squaredcircle