Along with the situational categories, tells must be categorized by hand-strength. The two basic hand- strength categories are Strong and Weak.
This is obviously a simplification. An opponent can have hands that are not clearly strong or weak. For example, they can have a decent hand that is vulnerable or a draw that’s strong.
Even when poker tells are at their most reliable, they only tell us how a player feels about his hand or what he intends to do. They can’t directly tell us the strength of the player’s hand. We have to infer, based on the situation and based on the type of player we’re playing with, what these tells mean.
For instance, some players who flop a good draw in Hold’em (for example, overcards and a flush draw) might give tells associated with having a good hand. They might bet with confidence on the flop. When you’re facing a pre-flop raiser and there are two diamonds on a Ten-high board, you have to take into account the fact that this guy could be betting confidently with a hand like AK of diamonds.
But that’s a problem usually only on the flop because the flop is, for the most part, the only place where a draw is going to be stronger than a made hand. When that same player who flopped a strong draw with AK of diamonds gets to the turn and doesn’t make his hand, his odds of hitting a hand have been almost cut in half. On the turn, with a slimmer chance of winning, he will be more likely to exhibit tells associated with a weak hand. If he gets to the river and still hasn’t made a hand and is now bluffing, he’s going to be even more likely to exhibit weak-hand tells.
Hand strength is usually relatively undefined on the flop. This is because of the possibility of draws. Additionally, in no-limit games, flop bets are smaller and less likely to produce emotion-based tells. These issues also often apply to the turn. This is why I tend to just play with my best fundamental strategy on the flop and turn, regardless of reads.
The river is a much different story, because there are no draws possible. So if you get a reliable read of strength or weakness, it will be more likely to mean something. In most cases a typical player, when he reaches the river, will usually have his own internal answer as to whether he wants action or doesn’t want action.
Pre-flop, in a no-limit game, can be similar to the river, because there are no meaningful draws possible. (You could call AK, AQ, etc. “drawing hands”, but in this instance I would not consider them “meaningful draws”.) Pre-flop is not nearly as reliable as the river, but with some players you can notice differences in their pre-flop behavior. For example, many players will feel ambivalent with most of their hands, but they will show signs of anxiety when they push all-in with junk, or show signs of relaxation when they push all-in with a high pair.
The reasons in the previous three paragraphs are why I tend to rely on emotion-based tells mostly for big river bets, and occasionally for big pre-flop bets.
Breaking tells into ‘strong’ and ‘weak’ categories is a simplification, but it is a necessary simplification. If you have a reliable read on someone, it will give you an answer to the question, “Does he want me to play or does he want me to fold?” In most situations, against most players, that will be very valuable information.