Well that much goes without saying, but there are ways to work in that sort of group training outside of gathering a full group to train at the same time. Double battles, for instance, or even the trainer working in a specific strategy. But if the old saying about younger minds learning faster than older ones holds true, there should be a notable difference between Pokemon who work together because they were trained in it after they were strong individually, and those who worked as a team from the beginning.
If there is no noticeable difference, this would imply that Pokmeon continue to hold the same capacity to retain knowledge for their full lifespan.
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If there is no noticeable difference, this would imply that Pokmeon continue to hold the same capacity to retain knowledge for their full lifespan.