Automatic Site Updating for Search Engine Optimisation

Hello,

A few days ago I watched some seminar tapes on web vending and promotion.
The person carrying out the seminar explained that one way to ensure increased page rank on Google was to regularly update your pages. His 'way around' this was to do this automatically. What he suggested was that the date on his website would update everyday so when the search engine returned it would see new content.

I may be wrong but I do not think this would work. I visited the guy's website and sure enough he has a Javascript for the Date. Thus when you view his site the date is always updated for the day. My opinion is that the search-engine would not 'view' the page but rather the code. The code as such would never change and thus the search engine would not in fact provide a higher ranking.

Am I correct in my thinking? I am wondering whether to add the script or not.