Sherbert,
You're hypothesizing from what may happen to a PLHE game to a PLO game. Firstly, the example of lots of players going allin is not useful. It happens very rarely, and almost never in live games. I am assuming of course that these are significant allins and not just tiny stack gambling ones. If the tight player has AA double suited he will not be a favourite to win the pot, but he will be very +EV. Cest la vie.
Your example of more realistic play is, not to be rude, a bit silly. If the LAG has 8 outs, why does this shoot up the tight player's variance. If my foe only has 8 pure outs to win I am happy to go allin every time. Variance in PLO is caused by 50-50 and 60-40 situations which happen all the time. But not as much to tight players. Remember your original post was that a tight player would have a bigger SD than a loose aggressive one in a loose game. I still don't see how you get this. The key point is that it is harder to push tight players around in PLO than in any other game, because 25% of hands, for example, would include a lot of hands like 4 card wraps, which will hit flops that a LAG may be inclined to push at.
gl
Dave
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