g1smd - 8:20 am on Mar 16, 2010 (gmt 0)
Yes, Matt was only talking about certain scenarios, but there are many others to consider.
- Single redirect within sub-domain (e.g. for 'named index' to '/' canonicalisation, or for moved content page)
- Single redirect within domain (e.g. non-www to www, and other types of canonicalisation)
- Single redirect cross-domain (e.g. example.com to newsite.com site move, or for .co.uk and .com canonicalisation)
- Multiple redirects within sub-domain (e.g. content page moved multiple times, or for stripping referrer/campaign parameters and loading a tracking cookie)
- Multiple redirects within domain (e.g. inadvertently chaining the rule for non-www to www canonicalisation and a rule for some other process)
- Multiple redirects across domains (e.g. for site that has moved multiple times)
- Combinations of the above making even longer chains (e.g. a 'named index' to '/' canonicalisation redirect within the old domain, followed by a non-www to www canonicalisation rule on the old domain, followed by a redirect to the same page on new domain, etc).
Add redirects that load cookies, and redirects that strip referrer/campaign parameters ahead of all this, and the visitor might be redirected four or five times from when they click a link, to when the content is actually served. I would not expect PageRank to survive that chasm.