[imported_Jim C]

Here it is, as described by W. Deranged:

Clarkmeister's Theorem: When playing a heads-up pot out-of-position, always lead the river if the river makes four-to-a-flush.

The idea--

If you have a big flush, it's obviously a value bet.

If you don't have a big flush:

1. Villain may fold a better, non-flush hand or a baby flush fearing a big flush.

2. Villain may call with a worse hand thinking you're full of it (it's one of those weird situations where there are both value-bet and bluff-bet reasons to bet).

3. You can easily fold to a raise.

4. You don't allow yourself to get bluffed out of pots when you do have the best hand (particularly as many will automatically bet the scare card if you check).

I (Jim) would add that this assumes a reasonable, thinking opponent. I've seen Party Poker fish raise and re-raise here with only a 5 or 6 of trump.

Anyhow, I think this is an excellent use of bet/fold.

Jim