Turn range interaction COvBU

Hi guys, the member Moulderick posted a hand in the Portuguese forums that I'd like to share with you because I think it illustrates well some mistakes you make on a daily basis at the micros:

Original de Moulderick
Hi!

BB: 20/17, Agg%: 35/47/38. hands: 240.

Poker Stars, $0.10/$0.25 No Limit Hold'em Cash, 6 Players
Poker Tools Powered By Holdem Manager - The Ultimate Poker Software Suite.

SB: $30.27 (121.1 bb)
BB: $26.69 (106.8 bb)
UTG: $13.48 (53.9 bb)
MP: $25 (100 bb)
Hero (CO): $25.22 (100.9 bb)
BTN: $12.05 (48.2 bb)

Preflop: Hero is CO with T J
2 folds, Hero raises to $0.75, BTN calls $0.75, SB folds, BB calls $0.50

Flop: ($2.35) J 2 T (3 players)
BB checks, Hero bets $1.50, BTN calls $1.50, BB calls $1.50

Turn: ($6.85) A (3 players)
BB checks, Hero bets $4.35, BTN folds, BB raises to $12.25, Hero folds

Results:

Spoiler

$15.55 pot ($0.70 rake)
Final Board: J 2 T A
BB mucked and won $14.85 ($8.25 net)
Hero mucked T J and lost (-$6.60 net)
BTN mucked and lost (-$2.25 net)

My opinion: We CANNOT value be turn!

Let's even ignore the BB completely, we'll get back to that later. Let's just imagine that we open pre flop, reg calls BU, BB folds, we cbet flop and and see this turn, heads up.

Do we have a value bet turn?

Board: J:spade: T:club: 2:heart: A:heart:
Equity Win Tie
MP2 39.20% 38.38% 0.82% { JhTs }
MP3 60.80% 59.99% 0.82% { TT, 22, AQs-ATs, KJs+, QJs, JTs, AQo-ATo, KJo+, QJo }

Even if we are generous and give villain all combos of QJo/KJo, we still don't have close to 50% equity to be able to value bet turn. This is important, we have two pair and we can't value bet turn. This is explained by the fact that the turn card helped villain's range tremendously, since now he has 16 combos of nuts (KQ) and all combos of better 2pair (AJ/AT). And this is definitely enough to prevent us from value betting our hand.

So what is the worst hand we can value bet? Well, if villain's range is close to what I assign him, a hand like AT is pretty close and AJ should be a value bet.

The situation gets even more funky when we check our JT on the turn and villain bets, it's actually a tough spot for us, since villain's range has very few bluff bets and that should mean we have a grimmer decision that you might expect. Anyways, villain should have enough 89s, K9s and the ocasional value bet with AQ for us to profitably x/c turn with JT.

Now, let's go back and analyze the original scenario, where we have a multi way situation. In that case our bet on the turn it's even worse, hands like QJ/KJ are clear folds for both players and that should mean our equity will drop a lot against their continuing range.

What have we learned from this hand?

[*] we have to get used to stop looking at our hand in absolute terms and force ourselves to think in villain's range, in our range and in the range interaction. The reverse also happens a lot, we sometimes don't make clear value bets because we look at our hand in absolute terms, and cbetting turn with second pair feels like a bad play when in a lot of situations it isn't.
[*] getting a feel for counting combos is a big deal. It should be clear that 30+ combos in villain's range crushes us on the turn, practicing this sort of thing helps make more accurate decisions on the fly at the tables