Early in my posting career here, I mentioned that as we all progress, we run across that one nugget of info here and there that brings something together.
The flush or flush draw on the board always freaks me out. Until this thread, I had never really worked out how close trips was to that flush draw. I would usually temper my bets fearing the flush filling. The OP here clarified the notion, and I have a new found respect for trips, which had seemed to suffer badly at the hands of the flushes. From either side of the equation, trips versus the flush draw or flush on board happens often enough that a good understanding of the odds is more important than in many hands. You can always know with the flush it is good if there is no pair showing. With trips or the hidden set, you can't be as sure the xxx will hold against the flush on the board.
So assume for a second that the odds, being as close as they are, assume they are exactly even. What then?
The flush on the board does offer more bluff opportunities than holding trips might. However, one can hold trips, and still execute the flush bluff. Only and A hi flush should come back at you. Any pair on the board should be able to bluff off a flush, even a made flush. But we know that seldom happens, whereas the flush bluff often takes down the pot.
I think it is because it is easier to quickly see the flush, where as the pair on the board is not defined. From the flushes POV, it could be 2 pair, or trips, or the boat. The flush beats 2 of those 3. So right off he sees he has 67% odds in his favor. He is betting at that pot.
The set on the other hand, sees the flush board, and at whatever street it is, that flush can beat his trips. He should probably proceed cautiously.
Bottom line here is that as OP has it set up, the flush is the more playable bluff. Holding the set is a damned if you do, and damned if you don't thing. The set is gold till that 3rd flush card hits. So, It is better to bluff the flush, while holding the set, than visa
Sorry Van, I had to work that out in my head before what you were really getting at made any sense to me.