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"Nobody's making games for the retired people" – The growing yet underserved market for grey gamers
(www.gamesindustry.biz)
This is a most excellent place for technology news and articles.
The alternative is the tutorial being accessible from within the game, like a manual. In no case the solution is "force the tutorial at the beginning of the game"
The skills learned in the tutorial aren't the ones that are forgotten when you take two weeks off late in the game. Redoing a tutorial wouldn't be the solution.