Shaddows - 7:37 am on Sep 6, 2012 (gmt 0)

You use robots.txt to keep Google off your page. It stops them knowing stuff. That's it.

Real-world reasons for employing it include, but are not limited to
- Preserving Crawl budget (CSS files might not need crawling)
- Blocking file directories (/images/)
- Creating bad spider lists (block a directory, link to it in a hidden link, ban anything that finds its way there)

Would not a person of ordinary intelligence interpret this to mean that a file in a roboted-out directory will stay out of the index, once removed?

Suggests that using the removal tool will noindex the page for 90 days, as long as the initial check verifies that the WMT User chose the right page. Verification by checking an independant real-world signal.

Implied is that WMT tool will check regularly after the initial 90 days to see the signal is still in place, and will return the page to SERPs if not.

I have never used that tool, so I would be interested if that is actually what happens