EllisDee:
I think that’s somewhat ameliorated, though probably not completely, by the fact that hard mode gives you a small extra chance to get a 2. You literally can’t get a 2 if your second guess doesn’t obey “super” hard mode rules. (Actual hard mode lets you reuse bad letters. “Super” hard mode is the idea of you can only guess words that could possibly be the answer, not counting the previous answers list.)
Right? I feel like they have to at some point. You can’t let it dwindle down to “There’s only four words left!”, y’know?
I like your idea of protecting the last 6 months or year on a rolling basis, and then allowing repeats of any answers from before that.
My approach is that as long as the 'bot in charge doesn’t say "That’s not a word! ", it’s a word. On a strategic level, I do avoid plurals and present-tense verbs.
So BOING might actually appear.