Twitter has changed...a lot. Although Sifter can reach back to the earliest Jack Dorsey Tweets, at least the undeleted ones, it cannot change the fact that Twitter created a very different stream of metadata over time. As the platform evolved, so too did the metadata attached to a Tweet.
Some good resources:
The Basics (for historical reference, now obsolete)
The PowerTrack Operators
New Gnip PowerTrack 2.0 Rules & Filtering
The Caveats (for historical reference, now obsolete)