Changing Site Title & Description Often

I was wondering what you think about this and how you think it effects your sites rankings if it does at all. I have one website which over the past couple of years have not consistently kept the same title and description because I have been either redirecting the domain to another site or just went in a new direction with it. Now the SERPS have spidered my changes all this time and have given the updated results in the engines, but I am wondering if doing this too much would hurt rankings or PR because your site changes too much. My belief is that if search engines are trying to provide the most relevant information possible, and you don't keep your website on the same topic for the long term, how will the search engines know to place your site properly?

What do you think about this?

why do you keep switching up the purpose of the domain... if it's a throwaway, it probably doesn't matter. but if you want it to be relevant to something, you ought to keep it that way.

Your approach is no different to a popular blog that changes every hour. SE spiders love this and frantically re-vist every day (hungry for new content).

The trick is offer the spiders revisions of your site daily.
Page name - Keep
Title - Change only if alot of the content has changed and is relevant
H1,H2 tags - change daily
Body content - change frequently as long as it is relevant to your page name & Title.
It is OK to change only chunks of the body and keep the rest static.

Your web stats will not lie.