Many of these mistakes cost 20% or more of the ante, or $1 of $5. Conversely, on the river, people frequently call with a bad kicker. On the flop, people check pairs, waiting to just call on the river. They’re very surprised to see me raise with J8s, or K5o. From what I’ve seen, people are very reluctant to raise pre-flop (4x) without a big pocket pair, or at least Ace + face.
Granted, my site is the first to publish strategy for post-flop play, but I thought that people would instinctively figure it out. I find that people play quite differently from basic strategy. Basic Strategy Card for Ultimate Texas Hold'em.