To add to kre8r's post, it's often done when:

- You're out of position.
- You have a hand you want to see a showdown with, but you don't want to pay alot for the priveledge.
- You think the villain will often bet when checked to and may bet up to pot size.
- You don't think the villain will bluff raise that often.
- You think you can get some value out of worse hands that will call, that would have otherwise folded to a larger bet.

As for size, I think 1/3 to 1/2 pot is fine.

My question though is, even though you do it against opponents less likely to bluff raise, surely these guys are eventually going to wake up and realise it's marginal hands wanting to see a showdown? With the games getting more aggressive these days and (at the lower stakes anyway) if it looks like a block bet it usually is, will we not see a ton more bluff raising in the future?

Am I right in thinking a standard TAG will pick these bets apart far too easily for them to be profitable?

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