I have this theory that whenever I change onsite things, my rankings go down a notch or two... but eventually go back up. Now -- I have NO evidence on this and in fact, not enough experience with this.. But, its just a thought.. anyone experience this?
Ok, here's the deal. The web and rankings do react like stock charts, and if you play stocks well you will read ranks - statistics well. When it goes down, it's because of an obvious reason, but what is the less obvious reasons it's lowering???Those are what you should focus on and expand upon.
Its probably going down from something you actually did many days previously and then rebounding on the next tweak. It is probably even more likely that it has been coincidence so far as you can have some keywords that constantly go up and down one position even if you do nothing.
Obviously, this is a long standing fact and everyone knows it (and makes total sense too, if you think about it). Also I will highly advice you to Never change the title of a well ranking page or else you will be doomed. Its kind of sad too as search engines are halting growth of Internet in some way.
Fact: Rankings react to anything you do with your website (from layout tweaking to backlinks) What you can do: Watch your own site through split testing. See which settings will give you higher rankings. No other person can do it. Unless you want to hire a researcher that is.
Every action has a equal and opposite (debatable) reaction, law of physics playing a crucial role in search engine rankings.
You can move up and down simply because another site is doing better or worse. It may or may not be anything you are doing someone else could have been tweaking (good or bad) on their own sites and it bumped you up or down to make room for them in their new spot. I have had onsite optimization play a big role in some client's websites as they didn't list for anything on their old site until I upload my redesign of their site and they list high within a week of google caching the new design. So it does make a difference.