The thing is, 99.999999% of the time (and I'm probably missing a few 9's) the engine does exactly the most optimal thing. However, database engines aren't perf

The thing is, 99.999999% of the time (and I'm probably missing a few 9's) the engine does exactly the most optimal thing. However, database engines aren't perfect -- I know I've encountered bugs in older SQL server versions where the query never finishes but making some trivial adjustments fixes it. This is a bug. And most mailing lists are filled with people encountering bugs. Saying what you want and getting the best result is exactly what you should expect.