[nhtool]

I had a hand last night in a NHLE cash game where I check-raised the turn on a four-straight board with the low end of the straight and the villain instantly reraised all in. I laid down my hand because he reraised me so quickly. When you check raise someone in a tight NLHE cash game and they don't even hesitate to come over the top, then I think that's a pretty strong tell that they've got a monster because 90% of the time they're beat and could easily get stacked unless they have something approximating the nuts.

That was my thinking at the time, until I remembered that in a lot of cases my super-quick bets and raises indicate that I have a medium-strength made hand with a strong redraw (i.e., top or middle pair with a straight/flush draw) and I want to be aggressive with it. I generally hesitate more when I have the nut made hand because I want to think about how to extract maximum value.

So, really, you never know that much based on someone's timing.

My conclusion after playing what must be millions of hands of online poker is that by-the-book timing tells are only reliable in rare situations, especially considering that so many players are multitabling and/or playing on crappy connections, but I do think we subconsciously pick up on things much more than we realize.