We're a few months into 2018 so this probably would have been better to post in early January but what would you guys(and gals) say is the most important poker concept/lesson that you've learned in the last year? Did you have an aha moment messing around with solvers or was your biggest take away from the last year something to do with your mental game? I'm curious as to what the community as a whole learned in the last 12 months...