I think it's very beneficial to be good at both. full ring will inevitably have lower swings and a nitty style can be very very profitable (ie. wota), so if you're getting the bad end of the variance stick at 6max and can't stand it, it is very useful to be able to switch to a lower variance style at least until you get your confidence back. Likewise if you become an action junky while playing full ring, being able to jump into a juicy 6max game and pwn is worthwhile.

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