[beatrix45]

The advice I once got from a white haired old guy named Oswald Jacoby was to preempt aggressively (or even psyche) against better opponents and to play straight down the middle against equal or weaker ones. The idea was to make the better players guess. They guess very well but do worse than if you just leave them alone. Of course, Jake himself usually played down the middle (unless he was behind and needed a board) since from his point of view there were no better players.

The pair in question is actually a (slightly) lesser pair at the very top levels of the game. I don't see statistical analysis as the way to go here. There are too many hard to measure variables involved (state of the match, quality of the opponents, feel of the table, etc.). Examining hand records from the round of 32 on of major championships might prove to be useful though.

[Lorne50]

Brian Senior published an analysis of the 1997 World Championships in Tunisia looking at all 2 and 3 level openers and comparing results for different meaning of the various bids. Frequency of each call was very low however but it may be worth looking at to give ideas about what to measure. The intro says he was planning to do it again at future events but I do not know if he did.