when is it good to play TPTK for stack and when is it a mistake ?
i think it's a big leak i have
posting hands is a good idea.
generally when passive players start raising into your TPTK you're often crushed.
very much depends on the board texture, type of aggressive player, etc. tons of factors go into it.
like i said, post hands.
Some TPTK or overpair hands are much stronger than others. In general, the higher the pair, the stronger the hand is. Also, coordination of the board weakens the pair. A♠6♠ on a board of 6♥5♥4♥ may not be worth playing, much less stacking off, but AK on an A62 board more often is.
Some ways to get a lot of money into the pot represent more strength than others. A bet and then a raise from a passive player in front of you may mean you should fold some TPTK hands when you would be happy to bet-bet-bet yourself.
In a raised pot with an effective stack depth of 50 bb, you should often be willing to get all-in with a strong top-pair hand.
If the pot is a 3-bet pot, then your opponents generally have tighter ranges. However, the decreased stack:pot ratio also means that you should fight harder for the pot and be more willing to stack off with TPTK in most situations. In a limped pot, you should be less eager to get all-in with one good pair.
If you decide that you want to get all-in, or are willing to get all-in, it is still possible that some lines are much better than others. You usually don't want to take a line which pays off all better hands and folds out all weaker hands, although that is sometimes acceptable if you are protecting your hand from some draws.