Leaving the legality to your own assessment/conscience; I would have thought doing a head and checking the headers for expiry information would reduce your overhead; though I'm not sure how that plays with in-page changes.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority". I knew I was on the right track :)
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Fast efficient webpage section monitoring by BrowserUk
in thread Fast efficient webpage section monitoring by Marcool

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