@ Old Geezer,
Generally, turtling is when one plays defensively and focuses on technology and using diplomacy instead of battling. Thus, a turtle would not attack any faction but generally would attack nearby rebels to gain a small empire. Once consolidated, the turtle would then look to its defenses and use diplomacy to stay out of conflicts. Also, the turtle needs to play a high chivalry game to keep their reputation up.
Personally, if I were purely turtling I would not go on crusades and would not attack enemy provinces except rebel. However, I never play my games like that but generally find them more enjoyable when I strike a balance. I prefer slow advances and dreadful generals.
Just my opinion.
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