Small 2,5x 3bets as a re-steal might be a very good way to counter a reg stealing from late position. But we have to pick our spots very carefully. For one thing, we want to be deeper, we usually pull this trick with small Ax or Kx type of hands that have a blocker effect to his stealing and 4betting range. We also have to balance our 3bets by raising the same size(2,5x) with both our bluffs and value stacking-off hands. We need to know for sure that villain is a competent player. I would never do this vs a station,some aggro fish or an unknown. They will call on our small 3bet IP a lot and we end up in a nasty spot playing a big pot with a marginal hand. Also, if the reg is really good, sooner or later he is gonna start adjusting by adding some bluffs to his 4betting range like small pairs and 89s type of hands. He is also likely to add 99, AQ to his value 4bet range.
However, I dislike bluff 3bet/fold in that spot. We are too short, only 17bb deep, once we re-raise, we are almost committed to call, not to mention the BTN is still an unknown, 66 hands sample is nothing. He might flat, he might push, either way we lose a big portion of our stack or end up in a nasty spot. Once again- you only use the 2,5x 3bet/bluff vs opponents who you know are decent. 25/17 doesn't say much by the way. It looks kinda fishy if it's not filtered for SH play. The most important criteria for these spots is the gap between his open stealing and calling range. The bigger the gap, the more hands we can profitably push. A fish for example is gonna raise/call a lot of hands, therefore we are only willing to 3bet shove with our value hands. If you think he raises the BTN a lot as he should (30-35%+), but only calls, let's say 88, AJ readless, then you can profitably shove any pair, any suited ace, A9-To+, many broadway hands, a lot of suited Kings, Queens and mid suited connectors. For me to re-steal that wide though, I need to have a very decent sample and reads. In that spot, if you think he's decent and raise/fold enough, go ahead and push. If you are unsure, folding won't hurt.
