Sklansky plays 300-600 3+ times a week.

I think NLHE can be beaten by a system at the worst levels simply because you can fold every hand but AA KK QQ AK JJ preflop and push those and get called by worse hands enough to make it profitable. Maybe fold JJ behin a raise.
In Limit it would be a lot more complex.

SnG I can play 5 straight and maybe have to use my brain twice.

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