I want to be clear that I'm not referring to a re-crawl, but a re-index. Now I realize there are a gazillion ranking signals and most of the stronger signals are probably not on-page signals (although page title, headers, and anchor text *combined* is probably a relatively strong signal) so that for most situations, on-page changes are going to like move you from the middle of page 2 to top 3 (except for obscure - low competition long tail keywords of course.)
So is there a delay between re-crawl and re-rank (I'll use that term instead of re-index). I also realize the rank can change based on changes on the other sites in the SERPS. I suppose the re-rank delay could be verified by taking a 'sacrificial' page and totally changing the title, headings, and other on-page items to a completed different keyword theme and see how long it takes for the rank to go down for the previous keyword theme and up for the new theme.
I would think Google would quite possibly add a delay, even a random delay length, to discourage people from constantly requesting re-indexing of a single page to see the rank change. Granted the change if any would be small since on-page signals as I mentioned are a sliver of the signal pie. So most SEO's I would think would be of the opinion this 'trial-and-error' is a waste of time?
So is there a delay between re-crawl and re-rank (I'll use that term instead of re-index). I also realize the rank can change based on changes on the other sites in the SERPS. I suppose the re-rank delay could be verified by taking a 'sacrificial' page and totally changing the title, headings, and other on-page items to a completed different keyword theme and see how long it takes for the rank to go down for the previous keyword theme and up for the new theme.
I would think Google would quite possibly add a delay, even a random delay length, to discourage people from constantly requesting re-indexing of a single page to see the rank change. Granted the change if any would be small since on-page signals as I mentioned are a sliver of the signal pie. So most SEO's I would think would be of the opinion this 'trial-and-error' is a waste of time?